Shakeri Fatemeh, Shojai Abolfath, Golalipour Masoud, Rahimi Alang Somaye, Vaez Hamid, Ghaemi Ezzat Allah
Islamic Azad University of Lahijan, Lahijan, Iran.
Int J Microbiol. 2010;2010. doi: 10.1155/2010/351397. Epub 2010 Aug 31.
Protein A of Staphylococcus aureus is a pathogenic factor whose encoding gene, spa, shows a variation in length in different strains. In this study the spa gene variation in S. aureus isolated from healthy carriers and patients was studied, We also compared this variation among MRSA with MSSA strains. 208 strains of Staphylococcus aureus which we were isolated from Gorgan, north of Iran were studied, 121 cases from patients and 87 cases from healthy carriers, 59 out of them were MRSA and 149 MSSA. Samples DNA were extracted and amplified by specific primer of spa gene. In 4 (3.8%) strains of them no spa gene was detected, and 10.6% had a dual band (1200 and 1400 bp). In strains with one band, the length of spa gene differed from 1150 to 1500 bp. The most prevalent length was 1350-1400 bp (37%). The frequencies of short spa bands (1150-1200 bp) in patients strains were significantly higher. In 4 (3.8%) strains of them no spa gene was detected, and 10.6% had a dual band (1200 and 1400 bp). In strains with one band, the length of spa gene differed from 1150 to 1500 bp. The most prevalent length was 1350-1400 bp (37%). The frequencies of short spa bands (1150-1200 bp) in patients strains were significantly higher. The spa gene length of 1350-1400 bp in MSSA was more than in MRSA strains (P < .05). The average length of spa in isolated strains from urinary tract infections was more than others. It is concluded that the length of spa gene depends either on resistance to Methicillin or the source of S. aureus isolation.
金黄色葡萄球菌的A蛋白是一种致病因子，其编码基因spa在不同菌株中的长度存在差异。本研究对从健康携带者和患者中分离出的金黄色葡萄球菌的spa基因变异进行了研究，我们还比较了耐甲氧西林金黄色葡萄球菌（MRSA）和甲氧西林敏感金黄色葡萄球菌（MSSA）菌株之间的这种变异。对从伊朗北部戈尔甘分离出的208株金黄色葡萄球菌进行了研究，其中121例来自患者，87例来自健康携带者，其中59株为MRSA，149株为MSSA。提取样本DNA并通过spa基因特异性引物进行扩增。其中4株（3.8%）未检测到spa基因，10.6%有两条带（1200和1400bp）。在有一条带的菌株中，spa基因长度在1150至1500bp之间有所不同。最常见的长度为1350 - 1400bp（37%）。患者菌株中短spa带（1150 - 1200bp）的频率明显更高。其中4株（3.8%）未检测到spa基因，10.6%有两条带（1200和1400bp）。在有一条带的菌株中，spa基因长度在1150至1500bp之间有所不同。最常见的长度为1350 - 1400bp（37%）。患者菌株中短spa带（1150 - 1200bp）的频率明显更高。MSSA中1350 - 1400bp的spa基因长度比MRSA菌株更多（P < 0.05）。从尿路感染中分离出的菌株中spa的平均长度比其他菌株更长。得出的结论是，spa基因的长度要么取决于对甲氧西林的耐药性，要么取决于金黄色葡萄球菌的分离来源。
