Endor Differentiates Complementary Roles for Active Site Histidines in (6–4) Photolyase
نویسندگان
چکیده
From the Freie Universität Berlin, Fachbereich Physik, Arnimallee 14, 14195 Berlin, Germany, the Department of Molecular Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, United States of America, the University College London, Department of Biology, Gower Street, London WC1E 6BT, United Kingdom, and the Kyoto University, Radiation Biology Center, Yoshidakonoe-cho, Sakyoku, Kyoto 606-8501, Japan
منابع مشابه
Electron nuclear double resonance differentiates complementary roles for active site histidines in (6-4) photolyase.
(6-4) photolyase catalyzes the light-dependent repair of UV-damaged DNA containing (6-4) photoproducts. Blue light excitation of the enzyme generates the neutral FAD radical, FADH., which is believed to be transiently formed during the enzymatic DNA repair. Here (6-4) photolyase has been examined by optical spectroscopy, electron paramagnetic resonance, and pulsed electron nuclear double resona...
متن کاملRole of two histidines in the (6-4) photolyase reaction.
The reaction mechanism of Xenopus (6-4) photolyase was investigated using several mutant enzymes. In the active site, which is homologous between the cis,syn-cyclobutane pyrimidine dimer and (6-4) photolyases, four amino acid residues that are specific to (6-4) photolyase, Gln(288), His(354), Leu(355), and His(358), and two conserved tryptophans, Trp(291) and Trp(398), were substituted with ala...
متن کاملStructural role of two histidines in the (6-4) photolyase reaction
Photolyases (PHRs) are DNA repair enzymes that revert UV-induced photoproducts, either cyclobutane pyrimidine dimers (CPD) or (6-4) photoproducts (PPs), into normal bases to maintain genetic integrity. (6-4) PHR must catalyze not only covalent bond cleavage, but also hydroxyl or amino group transfer, yielding a more complex mechanism than that postulated for CPD PHR. Previous mutation analysis ...
متن کاملLigation of the diiron site of the hydroxylase component of methane monooxygenase. An electron nuclear double resonance study.
Electron nuclear double resonance (ENDOR) spectroscopy is used to probe the coordination of the mixed valence (Fe(II).Fe(III)) diiron cluster of the methane monooxygenase hydroxylase component (MMOH-) isolated from Methylosinus trichosporium OB3b. ENDOR resonances are observed along the principal axis directions g1 = 1.94 and g3 = 1.76 from at least nine different protons and two different nitr...
متن کاملCrystal structure of a prokaryotic (6-4) photolyase with an Fe-S cluster and a 6,7-dimethyl-8-ribityllumazine antenna chromophore.
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 su...
متن کامل