应用蛋白质组学的方法分析缺铁培养对化脓性链球菌MGAS5005的影响

Proteomic analysis of effects of iron depletion on Streptococcus pyogenes MGAS5005

摘要:

【目的】研究铁缺失对化脓性链球菌的影响, 并寻找摄铁系统中的关键蛋白。【方法】以化脓链球菌为模型, 利用含Fe和不含Fe的培养基对细菌进行培养, 收集全细胞蛋白进行双向电泳, 定量软件分析电泳图谱, 质谱鉴定差异蛋白, 进而通过生物信息学分析蛋白上下游关系, 从中找到关键蛋白。【结果】鉴定出20个差异蛋白, 并用Cytoscape软件对差异蛋白相互关系网络进行节点分析找到其中5个瓶颈分子。【结论】在培养基中的Fe3+缺乏时, 细菌的生物合成和含氮化合物、生物大分子等重要代谢受到很大影响, 这为进一步阐明细菌铁代谢机制奠定了基础。

Abstract:

[Objective] Analyze the effects of iron deficiency on Streptococcus pyogenes, and find the key proteins in the iron acquisition systems. [Methods] Streptococcus pyogenes was cultured in THY medium with or without iron. Total proteins were extracted for the 2DE-gel analysis. The altered proteins upon iron depletion were identified by mass spectrometry. Further bioinformatics analyzed the relationship between key differentially expressed proteins. [Results] The 20 alterated protein were identified. With Cytoscape analysis of the betweenness of these proteins, 5 bottleneck proteins were detected. [Conclusion] The results showed that iron depletion affect the cellular biosynthetic processes, the metabolic process of compound containing nitrogen and the macromolecular metabolic process etc. This study laid a foundation for further studying the mechanisms of the iron metabolism in bacteria.