4dja

Publication Abstract from PubMed

The (6-4) photolyases use blue light to reverse UV-induced (6-4) photoproducts in DNA. This (6-4) photorepair was thought to be restricted to eukaryotes. Here we report a prokaryotic (6-4) photolyase, PhrB from Agrobacterium tumefaciens, and propose that (6-4) photolyases are broadly distributed in prokaryotes. The crystal structure of photolyase related protein B (PhrB) at 1.45 A resolution suggests a DNA binding mode different from that of the eukaryotic counterparts. A His-His-X-X-Arg motif is located within the proposed DNA lesion contact site of PhrB. This motif is structurally conserved in eukaryotic (6-4) photolyases for which the second His is essential for the (6-4) photolyase function. The PhrB structure contains 6,7-dimethyl-8-ribityllumazine as an antenna chromophore and a [4Fe-4S] cluster bound to the catalytic domain. A significant part of the Fe-S fold strikingly resembles that of the large subunit of eukaryotic and archaeal primases, suggesting that the PhrB-like photolyases branched at the base of the evolution of the cryptochrome/photolyase family. Our study presents a unique prokaryotic (6-4) photolyase and proposes that the prokaryotic (6-4) photolyases are the ancestors of the cryptochrome/photolyase family.

Crystal structure of a prokaryotic (6-4) photolyase with an Fe-S cluster and a 6,7-dimethyl-8-ribityllumazine antenna chromophore.,Zhang F, Scheerer P, Oberpichler I, Lamparter T, Krauss N Proc Natl Acad Sci U S A. 2013 Apr 30;110(18):7217-22. doi:, 10.1073/pnas.1302377110. Epub 2013 Apr 15. PMID:23589886^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.