Table_7_Comparative Genomic Analysis of the Human Pathogen Wohlfahrtiimonas Chitiniclastica Provides Insight Into the Identification of Antimicrobial Resistance Genotypes and Potential Virulence Traits.xlsx

Recent studies suggest that Wohlfahrtiimonas chitiniclastica may be the cause of several diseases in humans including sepsis and bacteremia making the bacterium as a previously underappreciated human pathogen. However, very little is known about the pathogenicity and genetic potential of W. chitiniclastica; therefore, it is necessary to conduct systematic studies to gain a deeper understanding of its virulence characteristics and treatment options. In this study, the entire genetic repertoire of all publicly available W. chitiniclastica genomes was examined including in silico characterization of bacteriophage content, antibiotic resistome, and putative virulence profile. The pan-genome of W. chitiniclastica comprises 3819 genes with 1622 core genes (43%) indicating a putative metabolic conserved species. Furthermore, in silico analysis indicated presumed resistome expansion as defined by the presence of genome-encoded transposons and bacteriophages. While macrolide resistance genes macA and macB are located within the core genome, additional antimicrobial resistance genotypes for tetracycline (tetH, tetB, and tetD), aminoglycosides (ant(2’’)-Ia, aac(6’)-Ia,aph(3’’)-Ib, aph(3’)-Ia, and aph(6)-Id)), sulfonamide (sul2), streptomycin (strA), chloramphenicol (cat3), and beta-lactamase (blaVEB) are distributed among the accessory genome. Notably, our data indicate that the type strain DSM 18708T does not encode any additional clinically relevant antibiotic resistance genes, whereas drug resistance is increasing within the W. chitiniclastica clade. This trend should be monitored with caution. To the best of our knowledge, this is the first comprehensive genome analysis of this species, providing new insights into the genome of this opportunistic human pathogen.

近期研究表明，嗜几丁质沃氏菌（Wohlfahrtiimonas chitiniclastica）可能是引发人类多种疾病的病原菌，包括败血症（sepsis）与菌血症（bacteremia），该菌此前被低估为人类致病原。然而，目前对嗜几丁质沃氏菌的致病性与遗传潜力所知甚少，因此有必要开展系统性研究，以深入解析其毒力特征与治疗方案。本研究对所有公开可获取的嗜几丁质沃氏菌基因组进行了全面分析，包括对其噬菌体（bacteriophage）组分、抗生素耐药组（antibiotic resistome）及潜在毒力谱的生物信息学表征。嗜几丁质沃氏菌的泛基因组（pan-genome）包含3819个基因，其中1622个为核心基因（core genes，占比43%），提示该菌为代谢保守的物种。此外，生物信息学分析显示，该菌的耐药组存在扩增现象，这一点可由基因组编码的转座子（transposons）与噬菌体的存在得到佐证。大环内酯类（macrolide）耐药基因macA与macB位于核心基因组中，而其余抗菌药物耐药基因型包括：四环素类（tetracycline）耐药基因tetH、tetB、tetD，氨基糖苷类（aminoglycosides）耐药基因ant(2'')-Ia、aac(6')-Ia、aph(3'')-Ib、aph(3')-Ia及aph(6)-Id，磺胺类（sulfonamide）耐药基因sul2，链霉素（streptomycin）耐药基因strA，氯霉素（chloramphenicol）耐药基因cat3，以及β-内酰胺酶（beta-lactamase）基因blaVEB，均分布于附属基因组（accessory genome）中。值得注意的是，本研究数据显示，模式菌株（type strain）DSM 18708^T未携带任何其他临床相关的抗生素耐药基因，但嗜几丁质沃氏菌进化枝（clade）内的耐药性正持续上升。需对该趋势保持警惕并密切监测。据我们所知，本研究是首次对该物种开展的全面基因组分析，为解析这一机会致病性人类病原菌的基因组特征提供了新的认知。