摘要

       本研究的目的是探讨一株从糖尿病患者中恢复的新型临床舍瓦氏菌（Shewanella sp.）株（Shew256）多药耐药（MDR）表型的分子机制。利用Illumina MiSeq-I和Nextera XT DNA文库进行全基因组鸟枪测序。用铁锹重新组装。利用RAST服务器对开放阅读帧进行预测，并用BLAST进行验证。利用平均核苷酸同源性（ANI）、ACT（Artemis）、OrthoMCL、ARG-ANNOT、ISfinder、PHAST、tRNAscan-SE、质粒pades、质粒finder和MAUVE进行了进一步的基因组分析。并进行了PCR和质粒提取。基因组分析显示，与其他Shewanella基因组相比，Shew256共有456个预测基因。此外，还发现了不同的抗性基因，包括blaPER-2。一个包含ISCR1基因的复杂的1类整合子被两个假定的转座酶基因打乱，被鉴定出来。此外，还发现了其他抗性基因，一个含有aph（3’）、插入序列、噬菌体和非编码rna的转座子。综上所述，我们观察到了获得能够解释MDR表型的抗性基因和移动元素的证据。这种舍瓦氏菌是一个典型的例子，说明了抗生素耐药性决定因素是如何被不常见的病原体获得的。

       The objective of this study was to investigate the molecular mechanisms explaining the multidrug-resistant (MDR) phenotype found in a novel clinical Shewanella sp. strain (Shew256) recovered from a diabetic patient. Whole-genome shotgun sequencing was performed using Illumina MiSeq-I and Nextera XT DNA library. De novo assembly was performed with SPAdes. RAST Server was used to predict the open-reading frames and the predictions were confirmed using BLAST. Further genomic analysis was carried out using average nucleotide identity (ANI), ACT (Artemis), OrthoMCL, ARG-ANNOT, ISfinder, PHAST, tRNAscan-SE, plasmidSPAdes, PlasmidFinder and MAUVE. PCR and plasmid extraction were also performed. Genomic analysis revealed a total of 456 predicted genes unique to Shew256 compared with other Shewanella genomes. Moreover, the presence of different resistance genes, including bla_PER-2, was found. A complex class 1 integron containing the ISCR1 gene, disrupted by two putative transposase genes, was identified. Furthermore, other resistance genes, a transposon containing aph(3'), insertion sequences, phages and non-coding RNAs were also found. In conclusion, evidence of acquisition of resistance genes and mobile elements that could explain the MDR phenotype were observed. This Shewanella sp. represents a prime example of how antibiotic resistance determinants can be acquired by uncommon pathogens.

        https://www.sciencedirect.com/science/article/abs/pii/S2213716517301170?via%3Dihub