Occurrence of methicillin-resistant Staphylococcus aureus strains from cattle and chicken, and analyses of their mecA, mecR1 and mecI genes
Occurrence of methicillin-resistant Staphylococcus aureus strains from cattle and chicken, and analyses of their mecA, mecR1 and mecI genes
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DOI：
10.1016/j.vetmic.2005.10.024
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发表时间：
2006-04-16
影响因子：
3.3
通讯作者：
Lee, JH
中科院分区：
文献类型：
--
作者：
Lee, JH
2001年至2005年，收集了牛、猪和鸡的各种样本并检查了耐甲氧西林（苯唑西林）金黄色葡萄球菌（MRSA）的存在。测试了 19 个样本的分离株是否存在 mecA 基因。通过确定这些分离株的 MIC，证实了甲氧西林耐药性。在这 19 个 mecA 阳性分离株中，有 16 个一致被发现对甲氧西林具有耐药性。在所有19个mecA阳性金黄色葡萄球菌中都发现了mecRI基因，并且在15个mecA阳性金黄色葡萄球菌中也检测到了mecI。 15 个 mecI 阳性分离株中，有 9 个的 mecI 基因与参考序列具有相同的序列。其他六种分离株中的三种在核苷酸 202 处具有 C 至 T 取代，一种在核苷酸 43 处具有 G 至 T 取代。这些先前已在人类 MRSA 中鉴定出。来自鸡的两个分离株在第 23 位添加了 C。MRSA 的这种突变尚未在其他地方报道过。在所有 15 个 mecI 阳性 MRSA 中，mec 启动子/操纵子区域的序列与参考序列相同。这表明除了 mecA、mecRI 和 mecI 基因之间的简单产物相互作用之外，还存在克服 mecI 引起的抗性抑制的其他机制。 (c) 2005 Elsevier B.V. 保留所有权利。
From 2001 to 2005, various specimens from cattle, pigs and chickens were collected and examined for the presence of methicillin (oxacillin)-resistant Staphylococcus aureus (MRSA). The isolates from 19 specimens were tested for the presence of the mecA gene. Methicillin resistance was confirmed by determining the MICs for these isolates. Among these 19 mecA-positive isolates, 16 were consistently found to be resistant to methicillin. The mecRI gene was found in all 19 mecA-positive S. aureus, and mecI was also detected in 15 of the mecA-positive S. aureus. The mecI gene had an identical sequence to the reference sequence in 9 of the 15 mecI-positive isolates. Three of the other six isolates had a C to T substitution at nucleotide 202, and one had a G to T substitution at nucleotide 43. These have been previously identified in MRSA from humans. Two isolates from chickens contained an addition of C at position 23. This mutation of MRSA has not been reported elsewhere. In all 15 mecI-positive MRSA, the sequence of the mec promoter/operator region was identical to the reference sequence. This suggests other mechanisms for overcoming the repression of resistance caused by mecI, beyond the simple product interaction between the mecA, mecRI and mecI genes. (c) 2005 Elsevier B.V. All rights reserved.