基于iTRAQ技术荧蒽降解菌的比较蛋白质组学分析

提取荧蒽不同诱导时间的红球菌BAP-1蛋白，应用iTRAQ技术结合LC-MS/MS对差异蛋白进行聚类以及生物信息学分析，以研究荧蒽高效降解菌的蛋白功能调控机理.结果表明：共鉴定到796个差异蛋白（差异倍数为2），其中表达上调的有613个，表达下调的有183个.3个比对组（3d/1d、6d/1d和8d/1d）共同差异表达蛋白为111个（上调56个，下调55个）.通过COG、GO富集和pathway富集分析后发现绝大部分差异蛋白参与代谢和能量产生过程.在荧蒽诱导下上调关键蛋白有细胞色素C、三磷酸腺苷合成酶、二磷酸核苷等激酶，还有一些结合蛋白、脱氢酶、核糖体蛋白和趋化性蛋白等；下调显著的是5-甲基四氢蝶酰三谷氨酸-同型半胱氨酸甲基转移酶.这些蛋白共同组成蛋白互作网络调控荧蒽降解菌的一系列生命活动.

iTRAQ-based comparative proteomic analysis of a fluoranthene-degrading bacterium

Comparative proteomics analysis was performed on proteins extracted from Rhodococcus sp. BAP-1on consecutive fluoranthene exposure days by using isobaric tags for relative and absolute quantization (iTRAQ) labeling and LC-MS/MS analysis to access differentially expressed proteins. In order to reveal the mechanism of the functional regulation of proteins in the fluoranthene-degrading bacterium, iTRAQ-based clustering and bioinformatics analysis detected a total of 796 differentially expressed proteins, including 613 up-regulated proteins and 183 down-regulated proteins. There were 111shared differentially expressed proteins in all three clusters (3d/1d, 6d/1d and 8d/1d). COG, GO enrichment and pathway enrichment analysis showed that most differentially expressed proteins were involved in the processes of metabolism and energy production. Induced by fluoranthene, the key over expressed proteins in this bacterial cells were cytochrome C, ATP synthase, nucleoside diphosphate and other kinases, some binding proteins, several dehydrogenases, ribosomal proteins and chemotaxis protein; the significant down-regulated proteins was 5-methyltetrahydropteroyltriglutamate-homocysteine methyltransferase. These all regulated proteins together formed protein interaction network to regulate a series of life activities of fluoranthene-degrading bacteria.