| Primary Identifier | IPR042493 | Type | Homologous_superfamily |
| Short Name | XPD_DNA_FeS |
| description | XPD belongs to a family of ATP-dependent helicases that are characterised by a 'D-E-A-H' motif []. This resembles the 'D-E-A-D-box' of other known helicases, which represents a special version of the B motif of ATP-binding proteins. In XPD, His replaces the second Asp.XPD is divided into four domains. The first three domains together with α-helix 22 from domain 4 form a donut-shaped structure containing a hole []. Domains 1 and 4 represent the RecA-like fold that is present in all helicases of superfamilies 1 and 2 (SF1 and SF2) []. Domains 2 and 3 are insertions, which emerge from domain 1. Domain 2 displays an exclusively α-helical architecture consisting of six α-helices and one 3-10 helix that surround the central 4Fe4S cluster. The FeS cluster is coordinated by four cysteines, consistent with the coordination typically observed in 4Fe4S clusters []. The FeS domain is vital for its helicase activity and might be involved in the damage recognition process [, , , ].This entry represents the FeS cluster domain found in XPD family members that are mostly from bacteria and archaea. |
