title: A new role of Deinococcus radiodurans RecD in antioxidant pathway.
abstract: In Deinococcus radiodurans, RecBCD holoenzyme is not intact because of the absence of RecB and RecC, but a RecD-like protein does indeed exist. In this work, D. radiodurans recD disruptant was constructed and its possible biological functions were investigated. The results showed that disruption of the recD gene of D. radiodurans resulted in a remarkably increased sensitivity to hydrogen peroxide but had no apparent effect on the resistance to gamma and UV radiation. Furthermore, complementation experiments showed that Escherichia coli RecD, helicase domain or N-terminal domain of D. radiodurans RecD could not individually restore the resistant phenotype to hydrogen peroxide of the recD disruptant, whereas the complete D. radiodurans RecD protein could. Further studies showed that D. radiodurans RecD took part in antioxidant process by stimulating catalase activity and reactive oxygen species scavenging activity in D. radiodurans. These results suggest that D. radiodurans RecD has a new role in the antioxidant pathway.
authors.affiliation: Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhou
authors.forename: Xinjue
authors.initials: X
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
authors.forename: Bujin
authors.initials: B
authors.lastname: Xu
authors.forename: Yuejin
authors.initials: Y
authors.lastname: Hua
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002374:Catalase / Q000378:metabolism; D034301:Deinococcus / Q000187:drug effects / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects; D004926:Escherichia coli / Q000235:genetics; D043211:Exodeoxyribonuclease V / Q000502:physiology*; D017353:Gene Deletion; D005816:Genetic Complementation Test; D006861:Hydrogen Peroxide / Q000494:pharmacology; D050296:Microbial Viability; D016254:Mutagenesis, Insertional; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors
chemical_list: D000900:Anti-Bacterial Agents; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D002374:Catalase; D043211:Exodeoxyribonuclease V