| Primary Identifier | IPR036821 | Type | Homologous_superfamily |
| Short Name | Peptide_deformylase_sf |
| description | Peptide deformylase (PDF) is an essential metalloenzyme required for the removal of the formyl group at the N terminus of nascent polypeptide chains in eubacteria: []. The enzyme acts as a monomer and binds a single metal ion, catalysing the reaction:N-formyl-L-methionine + H2O = formate + methionyl peptideCatalytic efficiency strongly depends on the identity of the bound metal []. These enzymes utilize Fe(II) as the catalytic metal ion, which can be replaced with a nickel or cobalt ion with no loss of activity. There are two types of peptide deformylases, types I and II, which differ in structure only in the outer surface of the domain. Because these enzymes are essential only in prokaryotes (although eukaryotic gene sequences have been found), they are a target for a new class of antibacterial agents [, , , ].The structure of these enzymes is known [, ]. PDF, a zinc metalloenzyme from the mitochondrion, comprises an active core domain of 147 residues and a C-terminal tail of 21 residue. The 3D fold of the catalytic core has been determined by X-ray crystallography and NMR. Overall, the structure contains a series of anti-parallel β-strands that surround two perpendicular α-helices. The C-terminal helix contains the characteristic HEXXH motif of metalloenzymes, which is crucial for activity. The helical arrangement, and the way the histidine residues bind the zinc ion, is reminiscent of metalloproteases such as thermolysin or metzincins. However, the arrangement of secondary and tertiary structures of PDF, and the positioning of its third zinc ligand (a cysteine residue), are quite different. These discrepancies, together with notable biochemical differences, suggest that PDF constitutes a new class of zinc-metalloenzymes []. |
