title: Crystal structure of a prokaryotic (6-4) photolyase with an Fe-S cluster and a 6,7-dimethyl-8-ribityllumazine antenna chromophore.
abstract: 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 Å 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.
authors.affiliation: Botanical Institute, Karlsruhe Institute of Technology, D-76131 Karlsruhe, Germany.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.forename: Patrick
authors.initials: P
authors.lastname: Scheerer
authors.forename: Inga
authors.initials: I
authors.lastname: Oberpichler
authors.forename: Tilman
authors.initials: T
authors.lastname: Lamparter
authors.forename: Norbert
authors.initials: N
authors.lastname: Krauß
mesh_terms: D016960:Agrobacterium tumefaciens / Q000201:enzymology*; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001665:Binding Sites; D055162:Biocatalysis; D018360:Crystallography, X-Ray; D019915:DNA Primase / Q000737:chemistry; D004255:Deoxyribodipyrimidine Photo-Lyase / Q000737:chemistry* / Q000378:metabolism; D019143:Evolution, Molecular; D007506:Iron-Sulfur Proteins / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D011621:Pteridines / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D040681:Structural Homology, Protein
chemical_list: D007506:Iron-Sulfur Proteins; D011621:Pteridines; C001061:6,7-dimethyl-8-ribityllumazine; D019915:DNA Primase; D004255:Deoxyribodipyrimidine Photo-Lyase