PprA: a novel protein from Deinococcus radiodurans that stimulates DNA ligation

• Published in: Molecular microbiology 2004-10, Vol.54 (1), p.278-285
• Main Authors: Narumi, Issay, Satoh, Katsuya, Cui, Suzhen, Funayama, Tomoo, Kitayama, Shigeru, Watanabe, Hiroshi
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Bacteriology; Base Sequence; Biological and medical sciences; Deinococcus - genetics; Deinococcus - metabolism; Deinococcus - radiation effects; Deinococcus radiodurans; DNA - genetics; DNA - metabolism; DNA Damage; DNA Ligases - genetics; DNA Ligases - metabolism; DNA Repair; DNA, Bacterial - genetics; DNA, Bacterial - metabolism; Escherichia coli; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Bacterial; Microbiology; Miscellaneous; Molecular Sequence Data; Mutation; Rec A Recombinases - metabolism
• ISSN: 0950-382X; 1365-2958
• DOI: 10.1111/j.1365-2958.2004.04272.x

Summary The extraordinary radiation resistance of Deinococcus radiodurans results from the efficient capacity of the bacterium to repair DNA double‐strand breaks. By analysing the DNA damage repair‐deficient mutant, KH311, a unique radiation‐inducible gene (designated pprA) responsible for loss of radiation resistance was identified. Investigations in vitro showed that the gene product of pprA (PprA) preferentially bound to double‐stranded DNA carrying strand breaks, inhibited Escherichia coli exonuclease III activity, and stimulated the DNA end‐joining reaction catalysed by ATP‐dependent and NAD‐dependent DNA ligases. These results suggest that D. radiodurans has a radiation‐induced non‐homologous end‐joining repair mechanism in which PprA plays a critical role.