title: Genetic and biochemical characteristics of the histone-like protein DR0199 in Deinococcus radiodurans.
abstract: Bacterial histone-like proteins are important for nucleoid structure, cell growth, DNA replication, recombination and gene regulation. In this study, we focused on the role of DR0199 (the EbfC orthologue), a newly identified member of the nucleoid-associated protein family in Deinococcus radiodurans. The survival fraction of DR0199-null mutant decreased by tenfold after treatment with 50 mM H(2)O(2), nearly sixfold at a 10 kGy dose of gamma ray and nearly eightfold at a UV exposure of 1000 J m(-2) compared with wild-type cells. The results of fluorescence labelling assays indicated that DR0199 protein localized in the nucleoid area of cells. Electrophoretic mobility shift assays demonstrated that D. radiodurans DR0199 is a DNA-binding protein. Furthermore, DNA protection assays suggested that DR0199 shields DNA from hydroxyl radical- and DNase I-mediated cleavage. The supercoiling of relaxed plasmid DNA in the presence of topoisomerase I revealed that DR0199 constrains DNA supercoils in vitro. Collectively, these findings suggest that DR0199 is a protein with DNA-protective properties and histone-like features that are involved in protecting D. radiodurans DNA from damage.
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Hu
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, 310016 Hangzhou, PR China.
authors.forename: Xiaoting
authors.initials: X
authors.lastname: Hua
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Ma
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Chen
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Xin
authors.initials: X
authors.lastname: Xu
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Liangyan
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Bing
authors.initials: B
authors.lastname: Tian
authors.affiliation: Key Laboratory for Nuclear-Agricultural Sciences of Chinese Ministry of Agriculture and Zhejiang Province, Institute of Nuclear-Agricultural Sciences, Zhejiang University, 310029 Hangzhou, PR China.
authors.forename: Yuejin
authors.initials: Y
authors.lastname: Hua
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004249:DNA Damage; D004269:DNA, Bacterial / Q000235:genetics; D004278:DNA, Superhelical / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D034301:Deinococcus / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D024202:Electrophoretic Mobility Shift Assay; D005720:Gamma Rays; D017353:Gene Deletion; D005816:Genetic Complementation Test; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008969:Molecular Sequence Data; D018384:Oxidative Stress; D016415:Sequence Alignment
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004278:DNA, Superhelical; D004268:DNA-Binding Proteins; D006861:Hydrogen Peroxide