克罗诺杆菌属食品分离株种水平鉴定方法比较研究
2020,32(5):503-508
摘要：目的 研究食品中分离克罗诺杆菌属种的鉴定方法,旨在建立稳定、可靠的种的鉴定方法。方法 本研究选择三种鉴定方法,包括生化鉴定(VITEK 2 Compact)法、基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)、全基因组测序,通过比较分析三种方法对19株克罗诺杆菌属 的鉴定结果,阐述三种鉴定方法的优缺点及其适用性。结果 本研究中19株克罗诺杆菌属的鉴定结果显示,VITEK 2 Compact对阪崎克罗诺杆菌和丙二酸盐克罗诺杆菌的鉴定准确率只有67%和66%,而MALDI-TOF MS和全基因组测序的鉴定结果一致,因此可以判定MALDI-TOF MS能够快速、准确、高通量对克罗诺杆菌属进行种的鉴定。但是MALDI-TOF MS受限于数据库,不能鉴定到亚种的水平。结论 本研究结果提示VITEK 2 Compact法不适用于克罗诺杆菌属种的鉴定；全基因组测序鉴定结果准确可靠；MALDI-TOF MS可以实现快速、高通量、准确的鉴定,仍需要进一步研究克罗诺杆菌属3个亚种的蛋白指纹图谱特点,丰富蛋白指纹图谱数据库,使其能够准确鉴定克罗诺杆菌属的7个种和3个亚种。
关键词：克罗诺杆菌属; 生化鉴定; 基质辅助激光解吸电离飞行时间质谱; 全基因组测序
Study on species identification of Cronobacter spp. in foods
Abstract:Objective To compare the species identification method of Cronobacter spp. in food, in order to establish rapid, high throughout identification method. Methods A total of 19 Cronobacter spp. in foods were identified with three method including biochemical method using VITEK 2.0 Compact, matrix assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS)and whole-genome sequencing (WGS). The advantages and disadvantages of the three identification method were analyzed. Results The result indicated that the accuracy of VITEK identification for C.sakazakii and C.malonaticus was 67% and 66% respectively. However, WGS and MALDI-TOF MS obtained the same result for 19 Cronobacter spp.. Three subspecies could not be identified by MALDI-TOF MS due to the limited database. Conclusion Biochemical method could not be used for species identification of Cronobacter spp. MALDI-TOF MS was rapid, high throughout and accurate, but still need to expand the fingerprint database for more Cronobacter spp. isolates.
Key words:Cronobacter spp.； biochemical method； matrix assisted laser desorption/ionization time of flight mass spectrometry； whole-genome sequencing
投稿时间：2020-06-01
基金项目：上海市第四轮公共卫生三年行动计划高端海外研修团队(GWTD2015S01)
