Sila Jaromir, Sauer Pavel, Kolar Milan
Department of Microbiology, Palacky University and University Hospital, Olomouc, Czech Republic.
Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2009 Sep;153(3):215-8. doi: 10.5507/bp.2009.036.
Staphylococcus aureus is an important pathogen characterised by its potential to express many virulence factors. Currently, special attention is being paid to methicillin-resistant strains of S. aureus (MRSA). The aim of this study was to compare the prevalence of 13 selected virulence factor genes in methicillin-resistant versus methicillin-susceptible S. aureus (MSSA) isolates and to investigate their accumulation in the same isolate.
Real-time PCR was used to detect the presence of genes in 200 isolates of S. aureus (100 MRSA and 100 MSSA) from the University Hospital Olomouc collected in 2005-2006.
Six out of the 13 monitored genes were detected more frequently in MRSA isolates: sea, seb, seg, sei, sej and eta, coding for the production of the enterotoxins A, B, G, I, J and the exfoliative toxin A. On the other hand, the pvl and tst genes coding for Panton-Valentine leukocidin and TSST-1 were more frequent in MSSA. Statistical analysis (chi-squared test) of the prevalence of virulence factors in the two groups showed a significant difference (P<0.05) in two cases (seg, sei).
A higher prevalence of selected virulence genes was not confirmed in the methicillin-resistant S. aureus group. This indicates no further increase in their threat.
金黄色葡萄球菌是一种重要的病原体，其特点是能够表达多种毒力因子。目前，耐甲氧西林金黄色葡萄球菌（MRSA）受到特别关注。本研究的目的是比较耐甲氧西林金黄色葡萄球菌与甲氧西林敏感金黄色葡萄球菌（MSSA）分离株中13种选定毒力因子基因的流行情况，并研究它们在同一分离株中的累积情况。
采用实时荧光定量PCR检测200株2005 - 2006年从奥洛穆茨大学医院收集的金黄色葡萄球菌（100株MRSA和100株MSSA）中基因的存在情况。
在MRSA分离株中，13个监测基因中有6个被更频繁地检测到：sea、seb、seg、sei、sej和eta，它们分别编码肠毒素A、B、G、I、J和剥脱毒素A的产生。另一方面，编码杀白细胞素和毒性休克综合征毒素-1的pvl和tst基因在MSSA中更为常见。两组毒力因子流行情况的统计分析（卡方检验）显示，在两种情况下（seg、sei）存在显著差异（P<0.05）。
耐甲氧西林金黄色葡萄球菌组未证实选定毒力基因的流行率更高。这表明它们的威胁没有进一步增加。
