空间诱导蜡状芽孢杆菌LCT-BC25和LCT-BC235的蛋白质组学研究

摘要

Objective To study the proteomics of Bacillus cereus mutant strains LCT-BC25 and LCT-BC235 by detecting the effect of space environment on them. Methods Space Bacillus cereus mutant strains LCT-BC25 and LCT-BC235 and ground control strain LCT-BC244 were identified with isobaric tags for relative and absolute quantitation(iTRAQ) by mass spectrometry. The detected peptides were reassembled and their functions were analyzed. The proteins with a significantly different expression were selected. Results The majority of the 1 269 possible proteins identified in this study were related with the bacterial metabolism according to the cluster of orthologous groups (COG), gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG). The proteomic analysis showed that the protein levels were up-regulated in space 57 and 8 mutant strains and down-regulated in 77 and 73 ground control LCT-BC244 strain. Conclusion The effect of space environment on Bacillus cereus mutant trains is not directional. Bacillus cereus can adapt to the space environment by adjusting its own metablism. The highly expressed hemolytic enterotoxin protein can influence the health of astronauts.%　　目的探索空间环境对蜡状芽孢杆菌的影响。方法采用同重同位素相对与绝对定量(isobaric tags for relativeand absolute quantitation,iTRAQ)技术对经空间诱变蜡状芽孢杆菌LCT-BC25和LCT-BC235以及地面对照株LCT-BC244进行蛋白质组质谱检测,对测得的肽段重新组装,对组装的蛋白进行功能注释分析,最终筛选具有明显表达差异的蛋白质。结果本研究共鉴定到1269个可能蛋白质,根据蛋白相邻类的聚簇(cluster of orthologous groups of proteins,COG)、基因本体论(gene ontology,GO)、京都基因与基因组百科全书(kyoto encyclopedia of genes and genomes,KEGG)对这些蛋白质进行分类分析发现,大多数鉴定到的蛋白与细菌代谢相关。比较蛋白质组学结果表明,空间诱变株LCT-BC25与地面对照株LCT-BC244比较,有57个蛋白上调,77个蛋白下调；空间诱变株LCT-BC235与地面对照株LCT-BC244比较,有8个蛋白上调,73个蛋白下调。结论空间环境对蜡状芽孢杆菌的影响具有不定向性,溶血性肠毒素蛋白明显高表达。