摘要

      目标：
      本研究报告了从西乔治亚州新分离的4株多重耐药鲍曼A.Baumani菌株（0830、0365、4022和2846）的基因组草图，以鉴定假定的抗微生物基因（ARGs）并确定本地临床分离株的克隆亚型。
       方法：
       利用Illumina MiSeq测序仪进行全基因组测序（WGS）。采用Vitek 2自动化系统进行微生物鉴定和耐药性分析。
       结果：
       经WGS鉴定为鲍曼假丝酵母。利用Oxford（Oxf）和Pasteur（Pas）多位点序列分型（MLST）方案，在电子分析中解决了它们的抗药性基因（ARG）含量和克隆相关性。菌株365和4022显示与ST944Oxf/ST78Pas相似的等位基因图谱。2846菌株显示了与ST19Pas/IC 1（国际或欧洲克隆I）一致的不同等位基因图谱，并展示了我们这里指定为1868的新牛津街。0830菌株显示了与3365和4022菌株相似的ST78Pas等位基因图谱，并且在牛津分型方案中还具有gpi基因的单一等位基因失配，从而导致ST1104Oxf等位基因图谱。
       结论：
       循环MDR-A.baumani表现出遗传异质性，基因组baumani抗性岛的结构和含量发生变化，并编码多个假定的arg。本报告是佐治亚州首例鲍曼多药耐药菌的克隆亚型信息和基因组特征，可能为今后的流行病学调查提供信息。

OBJECTIVES:

This study reports the draft genomes of four newly isolated multidrug resistant A. baumannii strains (0830, 0365, 4022 and 2846) from western Georgia to identify putative antimicrobial resistance genes (ARGs) and to determine the clonal subtypes of local clinical isolates.

METHODS:

An Illumina MiSeq sequencer was used to perform whole-genome sequencing (WGS). The Vitek 2 automated system was used for microbial identification and antimicrobial resistance profiling.

RESULTS:

Taxonomical identification as A. baumannii was confirmed by WGS. In silico analyses resolved their antibiotic resistance gene (ARG) content and clonal relatedness using the Oxford (Oxf) and Pasteur (Pas) multi-locus sequence typing (MLST) schemes. Strains 365 and 4022 displayed similar allelic profiles corresponding to ST944Oxf/ST78Pas. Strain 2846 displayed different allelic profile consistent with ST19Pas/IC 1 (International or European Clone I) and exhibited a novel Oxford ST we designate here as 1868. Strain 0830 displayed the ST78Pas allelic profile, similar to strains 3365 and 4022, and also possessed a single allelic mismatch in the gpi gene resulting in a ST1104Oxf allele profile in Oxford typing scheme.

CONCLUSION:

Circulating MDR A. baumannii exhibit genetic heterogeneity with variations in the structure and content of genomic A. baumannii resistance islands and encode multiple putative ARGs. This report represents the first clonal subtype information and genomic characterization of MDR A. baumannii in the country of Georgia and may inform future epidemiological investigations.