Characterization of BKC-1 Class A Carbapenemase from Klebsiella pneumoniae Clinical Isolates in Brazil

Author:

Nicoletti Adriana Giannini,Marcondes Marcelo F. M.,Martins Willames M. B. S.,Almeida Luiz G. P.,Nicolás Marisa F.,Vasconcelos Ana T. R.,Oliveira Vitor,Gales Ana Cristina

Abstract

ABSTRACTThreeKlebsiella pneumoniaeclinical isolates demonstrating carbapenem resistance were recovered from different patients hospitalized at two medical centers in São Paulo, Brazil. Resistance to all β-lactams, quinolones, and some aminoglycosides was observed for these isolates that were susceptible to polymyxin B. Carbapenem hydrolysis, which was inhibited by clavulanic acid, was observed for allK. pneumoniaeisolates that belonged to the same pulsed-field gel electrophoresis (PFGE) type and a novel sequence type (ST), ST1781 (clonal complex 442 [CC442]). A 10-kb nonconjugative incompatibility group Q (IncQ) plasmid, denominated p60136, was transferred toEscherichia colistrain TOP10 cells by electroporation. The full sequencing of p60136 showed that it was composed of a mobilization system, ISKpn23, the phosphotransferase aph3A-VI, and a 941-bp open reading frame (ORF) that codified a 313-amino acid protein. This ORF was namedblaBKC-1. BrazilianKlebsiellacarbapenemase-1 (BKC-1) showed a pI of 6.0 and possessed the highest identity (63%) with a β-lactamase ofSinorhizobium meliloti, an environmental bacterium. Hydrolysis studies demonstrated that purified BKC-1 not only hydrolyzed carbapenems but also penicillins, cephalosporins, and monobactams. However, the carbapenems were less efficiently hydrolyzed due to their very lowkcatvalues (0.0016 to 0.031 s−1). In fact, oxacillin was the best substrate for BKC-1 (kcat/Km, 53,522.6 mM−1s−1). Here, we report a new class A carbapenemase, confirming the diversity and rapid evolution of β-lactamases inK. pneumoniaeclinical isolates.

Publisher

American Society for Microbiology

Subject

Infectious Diseases,Pharmacology (medical),Pharmacology

Cited by 71 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3