Detection and genetic characterization of β-lactamases in Prevotella interrnedia and Prevotella nigrescens isolated from oral cavity infections and peritonsillar abscesses
Detection and genetic characterization of β-lactamases in Prevotella interrnedia and Prevotella nigrescens isolated from oral cavity infections and peritonsillar abscesses
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DOI：
10.1016/j.anaerobe.2015.01.007
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发表时间：
2015-06-01
期刊：
影响因子：
2.3
通讯作者：
Radice, Marcela
中科院分区：
文献类型：
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作者：
Fernandez-Canigia, Liliana;Cejas, Daniela;Radice, Marcela
对慢性牙周炎和牙周脓肿患者中普雷沃氏菌和黑化普雷沃氏菌进行了β -内酰胺耐药机制和β -内酰胺酶流行率的前瞻性分析。采用表型和基因型方法表征β -内酰胺酶及其编码基因和遗传背景。总体而言，有64%（16/25）的中间假体和23.8%（5/21）的黑黑假体产生了β -内酰胺酶（p < 0.01）。除慢性牙周炎后恢复的内酰胺酶产率（8/16）高于黑化假单胞菌（2/16）外，几乎所有牙周脓肿分离株均产β -内酰胺酶（8/9和3/3）。在这些分离株中检测到cfxA，但未检测到cepA和cblA，这些分离株先前被归类为β -内酰胺酶产生者。在这两个物种中，产生CNA的分离株比不产生CNA的分离株显示出更高的β -内酰胺mic。最常见的等位基因是cfxA2，其次是cfxA3和一个名为cfxA6的新等位基因变体。对三个cfxA变体的下游侧翼区域的分析揭示了与Tn4555的mobA的关联，表明它们定位于一个可移动元件。β -内酰胺耐药和cfxA携带率似乎不仅与细菌种类有关，而且与感染部位有关。(C) 2015 Elsevier Ltd.版权所有。
A prospective analysis on beta-lactam resistance mechanisms and beta-lactamase prevalence was conducted on Prevotella intermedia and Prevotella nigrescens recovered from patients with chronic periodontitis and peritonsillar abscesses. Both phenotypic and genotypic methods were performed to characterize the beta-lactamases, their coding genes and their genetic contexts. Overall, beta-lactamase production was observed in 64% (16/25) P. intermedia and 23.8% (5/21) P. nigrescens (p < 0.01). Besides higher beta-lactamase production rates were observed in P. intennedia (8/16) than in P. nigrescens (2/16) recovered from chronic periodontitis, almost all isolates from peritonsillar abscesses were producers (8/9 and 3/3, respectively). cfxA, but not cepA and cblA, was detected in those isolates, which were previously categorized as beta-lactamase producers. CNA producing isolates displayed higher beta-lactam MICs than non-producers in both species. The most frequent allele was cfxA2, followed by cfxA3 and a new allelic variant named cfxA6. The analysis of the downstream flanking region in the three cfxA variants revealed the association with mobA of Tn4555, suggesting their localization in a mobilizable element. beta-lactam resistance and cfxA carriage prevalence seems to be not only related to the bacterial species but also to the infection site. (C) 2015 Elsevier Ltd. All rights reserved.