Natural and Non‐natural Antenna Chromophores in the DNA Photolyase from Thermus Thermophilus

Abstract

X-ray crystallographic and functional analysis of the class I DNA photolyase from Thermus thermophilus revealed the binding of flavin mononucleotide (FMN) as an antenna chromophore. The binding mode of FMN closely coincides with the binding of a deazaflavin-like chromophore in the related class I DNA photolyase from Anacystis nidulans. Compared to the R46E mutant, which lacks a conserved arginine in the binding site for the antenna chromophore, the FMN-comprising holophotolyase exhibits an eightfold higher activity at 450 nm. The facile incorporation of the flavin cofactors 8-hydroxy-deazariboflavin and 8-iodo-8-demethyl-riboflavin into the binding site for the antenna chromophore paves the way for wavelength-tuning of the activity spectra of DNA photolyases by using synthetic flavins.

Crystal structure of a prokaryotic (6-4) photolyase with an Fe-S cluster and a 6,7-dimethyl-8-ribityllumazine antenna chromophore

“…3B). The binding sites for the dicyclic DMRL in PhrB and for the tricyclic antenna chromophores 8-hydroxy-7,8-didemethyl-5-deazariboflavin, FAD, or FMN in other photolyases (14,21,28) are in homologous positions (Fig. 2B).…”

Functional motifs in the (6-4) photolyase crystal structure make a comparative framework for DNA repair photolyases and clock cryptochromes

“…Two distinct antenna binding sites, for 5,10-methenyltetrahydrofolic acid (MTHF) and 8-hydroxy-5-deazaflavin (8-HDF), were identified from crystal structures of Esherichia coli and Anacystis nidulans CPD PHRs, respectively (35,36). Other flavins including FMN and FAD can also bind in the 8-HDF site (40,41). In the At64PHR structure, both potential antenna-binding sites are present, but display some sequence and structural changes.…”

Algal photoreceptors: in vivo functions and potential applications

“…They are activated by blue light and contain FAD as the catalytic chromophore and either methenyltetrahydrofolate (MTHF) or 8-hydroxy-7,8-didemethyl-5-deazariboflavin (8-HDF) as the second chromophore (Sancar 1994(Sancar , 2003. During last 1 3 few years, additional antenna cofactors such as FMN, FAD and 6,7-dimethyl-8-ribityl-lumazine have been identified in photolayses (Geisselbrecht et al 2012;Klar et al 2006;Ueda et al 2004). …”