Du Xin-jun, Han Ran, Li Ping, Wang Shuo
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China.
Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin University of Science and Technology, Tianjin 300457, China.
J Proteomics. 2015 Oct 14;128:344-51. doi: 10.1016/j.jprot.2015.08.013. Epub 2015 Aug 30.
Cronobacter is a genus of widespread, opportunistic, foodborne pathogens that can result in serious illnesses in at-risk infants because of their immature immunity and high dependence on powdered formula, which is one of the foods most often contaminated by this pathogen. However, limited information is available regarding the pathogenesis and the specific virulence factors of this species. In this study, the virulences of 42 Cronobacter sakazakii isolates were analyzed by infecting neonatal SD rats. A comparison of the typing patterns of the isolates enabled groups with close relationships but that exhibited distinct pathogenesis to be identified. Among these groups, 2 strains belonging to the same group but showing distinct virulences were selected, and 2-DE was applied to identify differentially expressed proteins, focusing on virulence-related proteins. A total of 111 protein spots were identified using matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF/TOF-MS), and 89 were successfully identified. Further analysis suggested that at least 11 of these proteins may be involved in the pathogenesis of this pathogen. Real-time PCR was carried out to further confirm the differential expression pattern of the genes, and the results indicated that the mRNA expression levels were consistent with the protein expression levels.
The virulence factors and pathogenesis of Cronobacter are largely unknown. In combination with animal toxicological experiments and subtyping results of C. sakazakii, comparative proteomics analysis was performed to comprehensively evaluate the differentially expressed proteins of two isolates that exhibited distinct virulence but were closely related. These procedures made it possible to identify the virulence-related of factors of Cronobacter. Among the 89 total identified proteins, at least 11 show virulence-related potential. This work provides comprehensive candidates for the further investigation of the pathogenesis of Cronobacter.
阪崎肠杆菌属是一类广泛存在的、机会性食源性病原体，可导致高危婴儿患重病，因为这些婴儿免疫力不成熟且高度依赖配方奶粉，而配方奶粉是最常被这种病原体污染的食品之一。然而，关于该菌种的发病机制和特定毒力因子的信息有限。在本研究中，通过感染新生SD大鼠分析了42株阪崎肠杆菌分离株的毒力。对分离株的分型模式进行比较，能够识别出关系密切但发病机制不同的组。在这些组中，选择了属于同一组但毒力不同的2株菌株，并应用二维电泳来鉴定差异表达的蛋白质，重点是与毒力相关的蛋白质。使用基质辅助激光解吸/电离飞行时间串联质谱（MALDI-TOF/TOF-MS）共鉴定出111个蛋白点，其中89个成功鉴定。进一步分析表明，这些蛋白中至少有11种可能参与该病原体的发病机制。进行实时PCR以进一步确认基因的差异表达模式，结果表明mRNA表达水平与蛋白质表达水平一致。
阪崎肠杆菌的毒力因子和发病机制在很大程度上尚不清楚。结合动物毒理学实验和阪崎肠杆菌的亚型分析结果，进行了比较蛋白质组学分析，以全面评估两株毒力不同但关系密切的分离株的差异表达蛋白。这些步骤使得鉴定出阪崎肠杆菌的毒力相关因子成为可能。在总共鉴定出的89种蛋白质中，至少有11种显示出毒力相关潜力。这项工作为进一步研究阪崎肠杆菌的发病机制提供了全面的候选对象。
