title: Radiation-Resistant Micrococcus luteus SC1204 and Its Proteomics Change Upon Gamma Irradiation.
abstract: To explore the radiation-resistance mechanisms in bacteria, a radiation-resistant strain SC1204 was isolated from the surrounding area of a (60)Co-γ radiation facility. SC1204 could survive up to 8 kGy dose of gamma irradiation and was identified as Micrococcus luteus by phylogenetic analysis of 16S rRNA gene sequences. Its proteomic changes under 2-kGy irradiation were examined by two-dimensional electrophoresis followed by MALDI-TOF-TOF/MS analysis. The results showed that at least 24 proteins displayed significant changes (p < 0.05) at expression level under the radiation stress, among which 22 were successfully identified and classified into the major functional categories of metabolism, energy production and conservation, translation, ribosomal structure, and biogenesis. Among these proteins, leucyl aminopeptidase involved in synthesis of glutathione was the most abundant induced protein during postirradiation recovery, indicating that anti-oxidation protection was the most important line of defense in SC1204 against radiation. The next abundant protein was phosphoribosyl aminoimidazole carboxamide formyltransferase/IMP cyclohydrolase (AICAR Tfase/IMPCH), the key enzyme in the biosynthetic pathway of purine that is anti-radiation compound. Other proteins changing significantly (p < 0.05) after radiation exposure included urocanate hydratase, dihydrolipoyl dehydrogenase, succinyl-CoA synthetase subunit alpha, phosphoglycerate kinase, cell division protein FtsZ, elongation factor Ts and Tu, translation elongation factor Tu and G, 30S ribosomal protein S1, histidyl-tRNA synthetase, and arginyl-tRNA synthetase, which were considered to be the key proteins in urocanate metabolism, tricarboxylic acid cycle, glycolysis, cell division process, and synthesis process of proteins. Therefore, these proteins may also play important roles in radiation resistance in M. luteus.
authors.affiliation: Key Laboratory of Bio-resources and Eco-environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, Sichuan, People's Republic of China.|Institute of Biology, Yibin University, Yibin, 644007, Sichuan, People's Republic of China.
authors.forename: Wuyuan
authors.initials: W
authors.lastname: Deng
authors.affiliation: Key Laboratory of Bio-resources and Eco-environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, Sichuan, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Sichuan Institute of Atomic Energy, Chengdu, Sichuan, 610066, People's Republic of China.|Irradiation Preservation Key Laboratory of Sichuan Province, Chengdu, 610066, Sichuan, People's Republic of China.
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.affiliation: Sichuan Institute of Atomic Energy, Chengdu, Sichuan, 610066, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.affiliation: Key Laboratory of Bio-resources and Eco-environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, Sichuan, People's Republic of China.
authors.forename: Wenting
authors.initials: W
authors.lastname: Wen
authors.affiliation: Key Laboratory of Bio-resources and Eco-environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, 610064, Sichuan, People's Republic of China. qunsun@scu.edu.cn.
authors.forename: Qun
authors.initials: Q
authors.lastname: Sun
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D005720:Gamma Rays; D016982:Micrococcus luteus / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects*; D010802:Phylogeny; D020543:Proteome / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001426:Bacterial Proteins; D020543:Proteome