应用基质辅助激光解吸电离飞行时间质谱研究细菌性血流感染的血清多肽指纹图谱

摘要

Objective To study the serum peptide fingerprint using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) technology,and find the different peaks with potential significance and establish the diagnosis model of Staphylococcus aureus and Escherichia coli bloodstream infection.Methods To establish ICR mice model of S.aureus and E.coli bloodstream infections,and collect serum samples.The serum samples were purified by weak cation exchange beads,the serum peptide fingerprint was recognized by using MALDI-TOF MS and BioExplorer software between infections group and normal control group.Results Compared with the normal control group,6 peptides were up-regulated,7 peptides downregulated and 8 peptides up-regulated first and then down-regulated in S.aureus infection group;And 5 peptides down-regulated,4 peptides down-regulated first and then up-regulated,and 8 peptides up-regulated first and then down-regulated in E.coli infection group.Conclusion MALDI-TOF MS combined with BioExplorer software may be used as a tool to study the serum peptides of S.aureus and E.coli bloodstream infection,effectively find significant peptides for establishing a diagnosis model of these two bacterial infections,and has a certain value for the diagnosis of bacterial bloodstream infection.%目的 应用基质辅助激光解吸电离飞行时间质谱系统(MALDI-TOF MS)分析金黄色葡萄球菌、大肠埃希菌引起的血流感染血清多肽指纹图谱,寻找差异多肽峰并建立相应的诊断模型.方法 建立ICR小鼠金黄色葡萄球菌、大肠埃希菌血流感染模型,收集血清标本,经弱阳离子交换磁珠纯化,MALDI-TOF MS检测及BioExplorer生物软件分析研究金葡菌感染组与正常对照组、大肠埃希菌感染组与正常对照组间血清多肽指纹图谱.结果 比较金葡菌感染组与正常对照组发现,表达上调的多肽有6个,表达下调的多肽有7个,表达呈先上调后下调的多肽有8个.比较大肠埃希感染组与正常对照组发现,表达下调的多肽有5个,表达呈先下调后上调的多肽有4个,表达呈先上调后下调的多肽有8个.结论 利用MALDI-TOF MS技术和BioExplorer软件研究大肠埃希菌和金黄色葡萄球菌血流感染的血清多肽,可以发现感染组与正常对照组间的差异多肽并有效地建立这两种细菌感染的诊断模型,对于细菌性血流感染的诊断具有一定的价值.