Photolyase of Myxococcus xanthus, a Gram-negative Eubacterium, Is More Similar to Photolyases Found in Archaea and Higher Eukaryotes than to Photolyases of Other Eubacteria

Abstract We report the identification of the gene encoding a DNA photolyase (phrA) from the Gram-negative eubacterium Myxococcus xanthus. The deduced amino acid sequence of M. xanthus photolyase indicates that the protein contains 401 amino acids (M 45,071). By comparison of the amino acid and DNA sequences with those of other known photolyases, it has been found that it is more similar to the deduced amino acid sequences of the photolyases of “higher” eukaryotes than to the photolyases of other eubacteria. Recombinant plasmids carrying M. xanthus phrA rescue the photoreactivation activity of an irradiated strain of Escherichia coli with a deletion in phrA. This rescue is light-dependent.