title: Pyrroloquinoline quinone and a quinoprotein kinase support γ-radiation resistance in Deinococcus radiodurans and regulate gene expression.
abstract: Deinococcus radiodurans is known for its extraordinary resistance to various DNA damaging agents including γ-radiation and desiccation. The pqqE:cat and Δdr2518 mutants making these cells devoid of pyrroloquinoline quinone (PQQ) and a PQQ inducible Ser/Thr protein kinase, respectively, became sensitive to γ-radiation. Transcriptome analysis of these mutants showed differential expression of the genes including those play roles in oxidative stress tolerance and (DSB) repair in D. radiodurans and in genome maintenance and stress response in other bacteria. Escherichia coli cells expressing DR2518 and PQQ showed improved resistance to γ-radiation, which increased further when both DR2518 and PQQ were present together. Although, profiles of genes getting affected in these mutants were different, there were still a few common genes showing similar expression trends in both the mutants and some others as reported earlier in oxyR and pprI mutant of this bacterium. These results suggested that PQQ and DR2518 have independent roles in γ-radiation resistance of D. radiodurans but their co-existence improves radioresistance further, possibly by regulating differential expression of the genes important for bacterial response to oxidative stress and DNA damage.
authors.affiliation: Molecular Biology Division, Bhabha Atomic Research Centre, Mumbai, India.
authors.forename: Yogendra Singh
authors.initials: YS
authors.lastname: Rajpurohit
authors.forename: Shruti Sumeet
authors.initials: SS
authors.lastname: Desai
authors.forename: Hari Sharan
authors.initials: HS
authors.lastname: Misra
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004249:DNA Damage; D004260:DNA Repair; D004269:DNA, Bacterial / Q000235:genetics / Q000528:radiation effects; D034301:Deinococcus / Q000235:genetics / Q000378:metabolism / Q000502:physiology* / Q000528:radiation effects*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005720:Gamma Rays; D015870:Gene Expression; D020869:Gene Expression Profiling / Q000379:methods; D015964:Gene Expression Regulation, Bacterial; D009154:Mutation; D018384:Oxidative Stress / Q000235:genetics; D045542:PQQ Cofactor / Q000235:genetics / Q000378:metabolism*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011836:Radiation Tolerance / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D045542:PQQ Cofactor; D011494:Protein Kinases