傅立叶变换红外光谱技术对6种致病性大肠埃希氏菌快速分型的研究

摘要

目的 建立肠致病性大肠埃希氏菌(EnteropathogenicE.coli,EPEC)、肠产毒性大肠埃希氏菌(Enterotoxigenic E.coli,ETEC)、肠侵袭性大肠埃希氏菌(Enteroinvasive E.coli,EIEC)、肠黏附性大肠埃希氏菌(Enteroadhesive E.coli,EAEC)、肠出血性大肠埃希氏菌(EnterohmorrhagicE.coli,EHEC),弥散粘附性大肠埃希氏菌(Diffusely adherent E.coli,DAEC)6种致病性大肠埃希氏菌的傅立叶变换红外光谱(Fourier transforminfrared spectroscopy,FT-IR)数据库及FT-IR分型方法.方法 应用FT-IR技术对6种致病性大肠埃希氏菌进行指纹图谱数据采集并对其进行基线校正、归一化等处理,应用化学计量学方法对光谱数据进行分析.结果 本研究建立了6种致病性大肠埃希氏菌的FT-IR光谱数据库,实现了对6种可疑目标大肠埃希氏菌鉴定;建立了主成分分析(principal component analysis,PCA)和分级聚类分析(hierarchical cluster analysis,HCA)2种模型,成功实现了对6种致病性大肠埃希氏菌的快速分型.结论 FT-IR分析方法快速、简便、易操作,结果重现性好,是一种鉴定6种致病性大肠埃希氏菌的有效方法.%Objective To establish Fourier transform infrared spectroscopy (FT-IR) database and a FT-IR classification method for 6 species of Escherichia coli (E.coli),including Enteropalhogenic E.coli (EPEC),Enterotoxigenic E.coli (ETEC),Enteroinvasive E.coli (EIEC),Enteroadhesive E.coli (EAEC),Enterohmorrhagic E.coli (EHEC) and Diffusely adherent E.coli (DAEC).Methods FT-IR fingerprint absorption spectra of 6 species of E.coli were collected,treated by baseline correction and vector normalization and so on,and then analyzed by chemometric methods.Results A standard FT-IR spectral library including 6 species of E.coli was created and could be used to identify the target E.coli;2 cluster models of principal component analysis (PCA) and hierarchical cluster analysis (HCA) were developed and could classify the 6 species of E.coIi successfully.Conclusion As a rapid,easy-to-use and accurate technique,FT-IR spectroscopy is an effective tool to differentiate and identify 6 species ofE.coli.