blaCTX-M genes in clinical Salmonella isolates recovered from humans in England and Wales from 1992 to 2003
blaCTX-M genes in clinical Salmonella isolates recovered from humans in England and Wales from 1992 to 2003
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DOI：
10.1128/aac.49.4.1319-1322.2005
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发表时间：
2005-04-01
影响因子：
4.9
通讯作者：
Liebana, E
中科院分区：
文献类型：
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作者：
Batchelor, M;Hopkins, K;Liebana, E
头孢噻肟酶（Cefotaximases，CTX-M）是一个快速增长的A类β-内酰胺酶家族，广泛存在于临床细菌中。基于对氨苄青霉素和头孢菌素的抗性，从278，308株沙门氏菌分离株中选择106株分离株，并对其进行进一步表征。14个分离株为bla（CTX-M）PCR阳性，这些分离株的头孢噻肟MIC>= 16 mg/L。此外，序列分析显示存在CTX-M9、-15或-17至-18型。所有14个分离株呈现不同的PFGE限制性图谱，尽管6个肠道沙门氏菌血清型Virchow分离株形成紧密簇。bla（CTX-M）遗传决定簇存在于类似于63、105和> 148 kb的可转移质粒中。质粒限制性内切酶分析表明，blaCTX-M基因的传播可能是由相似质粒在不同克隆间的水平转移和不同质粒间的基因转移引起的。我们发现，CTX-M酶已经出现在与国外旅行和国内获得性相关的社区获得性感染中。这是英国首次报道沙门氏菌中存在CTX-M酶。此外，它代表了肠道沙门氏菌血清型Stanley中的bla（CTX-M）基因和肠道沙门氏菌血清型Anatum、肠杆菌和鼠伤寒沙门氏菌中的bla（CTX-M-15）基因的首次报道。
Cefotaximases (CTX-M) are a rapidly growing class A beta-lactamase family that has been found among a wide range of clinical bacteria. One hundred and six isolates were selected from 278,308 Salmonella isolates based on resistance to ampicillin and cephalosporins and subjected to further characterization. Fourteen isolates were bla(CTX-M) PCR positive, and cefotaxime MICs for these isolates were >= 16 mg/liter. Furthermore, sequence analysis revealed the presence of type CTX-M9, -15, or -17 to -18. All 14 isolates presented different PFGE restriction profiles, although six Salmonella enterica serotype Virchow isolates formed a tight cluster. The bla(CTX-M) genetic determinants were present in transferable plasmids of similar to 63, 105, and > 148 kb. Plasmid restriction analysis showed that both horizontal transfer of similar plasmids among different clones and transfer of genes between different plasmids were likely mechanisms involved in the spread of blaCTX-M genes. We have found that CTX-M enzymes have emerged in community-acquired infections both linked to foreign travel and domestically acquired. This is the first report of a CTX-M enzyme in Salmonella in the United Kingdom. Also, it represents the first report of a bla(CTX-M) gene in Salmonella enterica serotype Stanley and a bla(CTX-M-15) gene in Salmonella enterica serotypes Anatum, Enteritidis, and Typhimurium.