Panton-Valentine leukocidin (pvl) toxin is an important virulence factor of Staphylococcus aureus. The main genes are coa and spa for distinguishing and typing of S. aureus isolates. The aim of this study was to investigate antibiotic resistance, presence of mecA and pvl genes, as well as epidemiological typing of these isolates according to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in clinical sample isolated from Rasht city, Iran. A total of 250 clinical samples have been isolated from different hospitals. First, isolates of S. aureus were identified through microbiological methods and their antibiotic sensitivity was determined by disk diffusion agar based on a standard method of Clinical and Laboratory Standards Institute. DNA was extracted by boiling and presence of pvl and mecA genes was investigated by PCR using specific primers. To type these isolates, amplification of fragments of coa and spa genes was done and restriction enzyme digestion pattern was determined by PCR-RFLP method. Among the 250 samples, 50 isolates belonged to S. aureus and results of antibiotic sensitivity showed that 68% (34 samples) of isolates were methicillin resistant. Frequency of mecA and pvl genes among S. aureus isolates were 60% (30 samples) and 20% (10 samples). The PCR of coa gene showed three patterns whereas that of spa gene showed two patterns for enzyme digestion. Result of PCR-RFLP using HaeIII enzymes for coa gene and Bsp1431 for spa gene showed three patterns for enzyme digestion. Recent studies indicated increase in the resistance of S. aureus to different antibiotics, which is a serious problem in the treatment of infections resulting from S. aureus in this region. The result of PCR of pvl showed high frequency of this gene in this region, and coa and spa typing by PCR-RFLP was a useful tool for typing of S. aureus isolates.

中文翻译：

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携带Panton-Valentine leukocidin基因的耐甲氧西林金黄色葡萄球菌的患病率和分子分型。

Panton-Valentine leukocidin（pvl）毒素是金黄色葡萄球菌的重要毒力因子。主要基因是coa和spa，用于区分和分类金黄色葡萄球菌。这项研究的目的是根据聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法，从拉什特市的临床样本中调查抗生素的耐药性，mecA和pvl基因的存在以及这些分离株的流行病学类型伊朗。从不同医院共分离出250个临床样品。首先，通过微生物学方法鉴定金黄色葡萄球菌的分离物，并根据临床和实验室标准协会的标准方法，通过圆盘扩散琼脂测定其抗生素敏感性。通过煮沸提取DNA，并使用特异性引物通过PCR研究pvl和mecA基因的存在。为了对这些分离物进行分型，对coa和spa基因的片段进行了扩增，并通过PCR-RFLP方法确定了限制酶消化模式。在250份样品中，有50株属于金黄色葡萄球菌，抗生素敏感性结果显示68％（34份样品）的菌株对甲氧西林具有抗药性。金黄色葡萄球菌分离株中mecA和pvl基因的频率分别为60％（30个样品）和20％（10个样品）。coa基因的PCR显示三种模式，而spa基因的PCR显示两种模式的酶消化。以HaaIII酶为coa基因和Bsp1431为spa基因的PCR-RFLP结果显示了三种酶切模式。最近的研究表明，金黄色葡萄球菌对不同抗生素的耐药性有所增加，这是该地区金黄色葡萄球菌感染治疗的一个严重问题。pvl的PCR结果显示该基因在该区域的频率很高，并且通过PCR-RFLP进行的coa和spa分型是用于金黄色葡萄球菌分离物分型的有用工具。