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Search results 101 to 143 out of 143 for Hscb

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0.034s
Type Details Score
Publication
First Author: Hwang DM
Year: 1996
Journal: J Mol Evol
Title: A modular domain of NifU, a nitrogen fixation cluster protein, is highly conserved in evolution.
Volume: 43
Issue: 5
Pages: 536-40
Publication
First Author: Sendra M
Year: 2007
Journal: FEBS Lett
Title: The SUF iron-sulfur cluster biosynthetic machinery: sulfur transfer from the SUFS-SUFE complex to SUFA.
Volume: 581
Issue: 7
Pages: 1362-8
Publication
First Author: Ollagnier-de-Choudens S
Year: 2004
Journal: J Biol Inorg Chem
Title: SufA/IscA: reactivity studies of a class of scaffold proteins involved in [Fe-S] cluster assembly.
Volume: 9
Issue: 7
Pages: 828-38
Publication
First Author: Seidler A
Year: 2001
Journal: Biochem Soc Trans
Title: Incorporation of iron-sulphur clusters in membrane-bound proteins.
Volume: 29
Issue: Pt 4
Pages: 418-21
Protein
Organism: Mus musculus/domesticus
Length: 163  
Fragment?: false
Protein
Organism: Mus musculus/domesticus
Length: 160  
Fragment?: false
Protein
Organism: Mus musculus/domesticus
Length: 209  
Fragment?: false
Protein
Organism: Mus musculus/domesticus
Length: 124  
Fragment?: false
Protein
Organism: Mus musculus/domesticus
Length: 136  
Fragment?: false
Publication
First Author: Cupp-Vickery JR
Year: 2004
Journal: J Mol Biol
Title: Crystal structure of IscA, an iron-sulfur cluster assembly protein from Escherichia coli.
Volume: 338
Issue: 1
Pages: 127-37
Publication
First Author: Yeo WS
Year: 2006
Journal: Mol Microbiol
Title: IscR acts as an activator in response to oxidative stress for the suf operon encoding Fe-S assembly proteins.
Volume: 61
Issue: 1
Pages: 206-18
Publication
First Author: Rangachari K
Year: 2002
Journal: FEBS Lett
Title: SufC hydrolyzes ATP and interacts with SufB from Thermotoga maritima.
Volume: 514
Issue: 2-3
Pages: 225-8
Publication
First Author: Giel JL
Year: 2006
Journal: Mol Microbiol
Title: IscR-dependent gene expression links iron-sulphur cluster assembly to the control of O2-regulated genes in Escherichia coli.
Volume: 60
Issue: 4
Pages: 1058-75
Publication
First Author: Ollagnier-de-Choudens S
Year: 2001
Journal: J Biol Chem
Title: Iron-sulfur cluster assembly: characterization of IscA and evidence for a specific and functional complex with ferredoxin.
Volume: 276
Issue: 25
Pages: 22604-7
Publication
First Author: Tokumoto U
Year: 2001
Journal: J Biochem
Title: Genetic analysis of the isc operon in Escherichia coli involved in the biogenesis of cellular iron-sulfur proteins.
Volume: 130
Issue: 1
Pages: 63-71
Publication
First Author: Morimoto K
Year: 2006
Journal: J Mol Biol
Title: The asymmetric IscA homodimer with an exposed [2Fe-2S] cluster suggests the structural basis of the Fe-S cluster biosynthetic scaffold.
Volume: 360
Issue: 1
Pages: 117-32
Publication
First Author: Abdel-Ghany SE
Year: 2005
Journal: Plant Physiol
Title: Iron-sulfur cluster biogenesis in chloroplasts. Involvement of the scaffold protein CpIscA.
Volume: 138
Issue: 1
Pages: 161-72
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents the IscA component of the ISC system for iron-sulphur cluster assembly. IscA is believed to act as a scaffold upon which 2Fe-2S clusters are assembled and subsequently transferred to ferredoxin [, , ]. This clade is limited to the proteobacteria.
Protein Domain
Type: Family
Description: This entry represents a group of iron-sulfur assembly proteins mainly from plants and cyanobacteria, including AtCPISCA (AT1G10500, ) from Arabidopsis. AtCPISCA has homology to bacterial IscA and SufA proteins that have a scaffold function during Fe-S cluster formation. It may serve as a scaffold in chloroplast Fe-S cluster assembly [].This clade is distinctive from the proteobacteria clade shown in . Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents the SufA protein of the SUF system of iron-sulphur cluster biosynthesis. SufA acts as a scaffold in which Fe and S are assembled into FeS clusters []. This system performs FeS biosynthesis even during oxidative stress and tends to be absent in obligate anaerobic and microaerophilic bacteria.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents the NifU protein from the NIF system that is involved in nitrogenase maturation.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents members of the SufR cyanobacterial protein family of transcriptional regulators that control the SUF system. In all cases, the sufR gene is encoded near SUF system genes but in the opposite direction. This DNA-binding protein belongs to the DeoR family of helix-loop-helix proteins. All members also have a probable metal-binding motif C-X(12)-C-X(13)-C-X(14)-C near the C terminus.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents proteins belonging to the Rrf2 family of transcriptional regulators and are found, typically, as the first gene of the SUF operon. They are found only in a subset of the genomes that encode the SUF system, including the genus Xanthomonas. The conserved location suggests an autoregulatory role.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry is a subset of the larger family. Many members of are candidate ring hydroxylating complex subunits. However, members of the narrower family defined here are all found as part of the FeS assembly SUF system locus, in a subset of SUF-positive proteobacteria.
Protein Domain
Type: Domain
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents the N-terminal of NifU and homologous proteins. NifU contains two domains: an N-terminal and a C-terminal domain () []. These domains exist either together or on different polypeptides, both domains being found in organismsthat do not fix nitrogen (e.g. yeast), so they have a broader significance in the cell than nitrogen fixation.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). TheSUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry describes IscR, an iron-sulphur binding transcription factor of the ISC iron-sulphur cluster assembly system []. The HTH-type transcriptional regulator IscR (iron-sulphur cluster regulator) regulates the transcription of several operons and genes involved in the biogenesis of Fe-S clusters and Fe-S-containing proteins. It is a transcriptional repressor of the iscRSUA operon, which is involved in the assembly of Fe-S clusters into Fe-S proteins. In its apoform, under conditions of oxidative stress or iron deprivation, it activates the suf operon, which is a second operon involved in the assembly of Fe-S clusters. It represses its own transcription [, ]. It is induced by oxidative stress conditions and iron starvation [].
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents SufB, which is part of the SUF system and forms a complex with SufBCD.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents SufD proteins that form part of the SufBCD complex in the SUF system. No specific functions have been assigned to these proteins.
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents SufC, which acts as an ATPase in the SUF system. SufC belongs to the ATP-binding cassette transporter family () but is no longer thought to be part of a transporter.The complex is reported as cytosolic or associated with the membrane [].
Protein Domain
Type: Family
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on thevarious FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents a distinct group of NifU-like proteins, always found with a NifS-like protein and restricted to species that lack a SUF system. Typically, NIF systems service a smaller number of FeS-containing proteins than do ISC or SUF. These proteins are often encoded near the mnmA gene, involved in the carboxymethylaminomethyl modification of U34 in some tRNAs (see ). While other NifU proteins are associated with nitrogen fixation, this family is not.
Protein Domain
Type: Domain
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents the C-terminal of NifU and homologous proteins. NifU contains two domains: an N-terminal () and a C-terminal domain []. These domains exist either together or on different polypeptides, both domains being found in organisms that do not fix nitrogen (e.g. yeast), so they have a broader significance in the cell than nitrogen fixation.
Protein Domain
Type: Homologous_superfamily
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents SufB and SufD proteins, which are homologous, and form part of the SufBCD complex in the SUF system []. SufB accepts sulfur transferred from SufE [], whereas SufD may play a role in iron acquisition [].
Protein Domain
Type: Family
Description: Iron-sulphur(FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents IscU from the ISC system, a homologue of the N-terminal region of NifU (NIF system), an Fe-S cluster assembly protein found mostly in nitrogen-fixing bacteria. IscU is a scaffold protein on which Fe-S clusters are assembled before transfer to apoproteins []. This family includes largely proteobacterial and eukaryotic forms and excludes the true NifU proteins from Klebsiella sp. and Anabaena sp. as well as the archaeal homologues.
Protein Domain
Type: Domain
Description: Iron-sulphur (FeS) clusters are important cofactors for numerous proteins involved in electron transfer, in redox and non-redox catalysis, in gene regulation, and as sensors of oxygen and iron. These functions depend on the various FeS cluster prosthetic groups, the most common being [2Fe-2S]and [4Fe-4S][]. FeS cluster assembly is a complex process involving the mobilisation of Fe and S atoms from storage sources, their assembly into [Fe-S]form, their transport to specific cellular locations, and their transfer to recipient apoproteins. So far, three FeS assembly machineries have been identified, which are capable of synthesising all types of [Fe-S]clusters: ISC (iron-sulphur cluster), SUF (sulphur assimilation), and NIF (nitrogen fixation) systems.The ISC system is conserved in eubacteria and eukaryotes (mitochondria), and has broad specificity, targeting general FeS proteins [, ]. It is encoded by the isc operon (iscRSUA-hscBA-fdx-iscX). IscS is a cysteine desulphurase, which obtains S from cysteine (converting it to alanine) and serves as a S donor for FeS cluster assembly. IscU and IscA act as scaffolds to accept S and Fe atoms, assembling clusters and transfering them to recipient apoproteins. HscA is a molecular chaperone and HscB is a co-chaperone. Fdx is a [2Fe-2S]-type ferredoxin. IscR is a transcription factor that regulates expression of the isc operon. IscX (also known as YfhJ) appears to interact with IscS and may function as an Fe donor during cluster assembly [].The SUF system is an alternative pathway to the ISC system that operates under iron starvation and oxidative stress. It is found in eubacteria, archaea and eukaryotes (plastids). The SUF system is encoded by the suf operon (sufABCDSE), and the six encoded proteins are arranged into two complexes (SufSE and SufBCD) and one protein (SufA). SufS is a pyridoxal-phosphate (PLP) protein displaying cysteine desulphurase activity. SufE acts as a scaffold protein that accepts S from SufS and donates it to SufA []. SufC is an ATPase with an unorthodox ATP-binding cassette (ABC)-like component. SufA is homologous to IscA [], acting as a scaffold protein in which Fe and S atoms are assembled into [FeS]cluster forms, which can then easily be transferred to apoproteins targets.In the NIF system, NifS and NifU are required for the formation of metalloclusters of nitrogenase in Azotobacter vinelandii, and other organisms, as well as in the maturation of other FeS proteins. Nitrogenase catalyses the fixation of nitrogen. It contains a complex cluster, the FeMo cofactor, which contains molybdenum, Fe and S. NifS is a cysteine desulphurase. NifU binds one Fe atom at its N-terminal, assembling an FeS cluster that is transferred to nitrogenase apoproteins []. Nif proteins involved in the formation of FeS clusters can also be found in organisms that do not fix nitrogen [].This entry represents SufB and SufD proteins, which are homologous, and form part of the SufBCD complex in the SUF system []. SufB accepts sulfur transferred from SufE [], whereas SufD mayplay a role in iron acquisition [].This domain is found at the N-terminal part of the SufB and SufD proteins, which has a right-handed parallel beta helix structure [].
Publication
First Author: Layer G
Year: 2007
Journal: J Biol Chem
Title: SufE transfers sulfur from SufS to SufB for iron-sulfur cluster assembly.
Volume: 282
Issue: 18
Pages: 13342-50
Publication
First Author: Saini A
Year: 2010
Journal: Biochemistry
Title: SufD and SufC ATPase activity are required for iron acquisition during in vivo Fe-S cluster formation on SufB.
Volume: 49
Issue: 43
Pages: 9402-12
Publication
First Author: Hirabayashi K
Year: 2015
Journal: J Biol Chem
Title: Functional Dynamics Revealed by the Structure of the SufBCD Complex, a Novel ATP-binding Cassette (ABC) Protein That Serves as a Scaffold for Iron-Sulfur Cluster Biogenesis.
Volume: 290
Issue: 50
Pages: 29717-31
Protein
Organism: Mus musculus/domesticus
Length: 255  
Fragment?: false
Protein
Organism: Mus musculus/domesticus
Length: 256  
Fragment?: false
Publication
First Author: Schwartz CJ
Year: 2001
Journal: Proc Natl Acad Sci U S A
Title: IscR, an Fe-S cluster-containing transcription factor, represses expression of Escherichia coli genes encoding Fe-S cluster assembly proteins.
Volume: 98
Issue: 26
Pages: 14895-900
Publication
First Author: Gerhard DS
Year: 2004
Journal: Genome Res
Title: The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).
Volume: 14
Issue: 10B
Pages: 2121-7
Publication
First Author: Huttlin EL
Year: 2010
Journal: Cell
Title: A tissue-specific atlas of mouse protein phosphorylation and expression.
Volume: 143
Issue: 7
Pages: 1174-89
Publication
First Author: Church DM
Year: 2009
Journal: PLoS Biol
Title: Lineage-specific biology revealed by a finished genome assembly of the mouse.
Volume: 7
Issue: 5
Pages: e1000112