Huang Jinhu, Ma Jiale, Shang Kexin, Hu Xiao, Liang Yuan, Li Daiwei, Wu Zuowei, Dai Lei, Chen Li, Wang Liping
Laboratory of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
Department of Veterinary Microbiology and Preventive Medicine, Iowa State University Ames, IA, USA.
Front Cell Infect Microbiol. 2016 Oct 7;6:118. doi: 10.3389/fcimb.2016.00118. eCollection 2016.
is a previously neglected, newly emerging multidrug-resistant zoonotic pathogen. Mobile genetic elements (MGEs) play a key role in intra- and interspecies horizontal transfer of antimicrobial resistance (AMR) determinants. Although, previous studies showed the presence of several MGEs, a comprehensive analysis of AMR-associated mobilome as well as their interaction and evolution has not been performed. In this study, we presented the AMR-associated mobilome and their insertion hotspots in . Integrative conjugative elements (ICEs), prophages and tandem MGEs were located at different insertion sites, while 86% of the AMR-associated MGEs were inserted at and loci. Comprehensive analysis of insertions at and loci among four pathogenic species (, and ) revealed the existence of different groups of MGEs, including Tn5252, ICE1108, and TnGBS2 groups ICEs, Φm46.1 group prophage, ICE_ICE and ICE_prophage tandem MGEs. Comparative ICE genomics of ICE2603 family revealed that module exchange and acquisition/deletion were the main mechanisms in MGEs' expansion and evolution. Furthermore, the observation of tandem MGEs reflected a novel mechanism for MGE diversity. Moreover, an competition assay showed no visible fitness cost was observed between different MGE-carrying isolates and a conjugation assay revealed the transferability of ICE2603 family of ICEs. Our statistics further indicated that the prevalence and diversity of MGEs in is much greater than in other three species which prompted our hypothesis that is probably a MGEs reservoir for other streptococci. In conclusion, our results showed that acquisition of MGEs confers not only its capability as a multidrug resistance pathogen, but also represents a paradigm to study the modular evolution and matryoshkas of MGEs.
是一种先前被忽视的新出现的多重耐药性人畜共患病原体。移动遗传元件(MGEs)在抗菌药物耐药性(AMR)决定因素的种内和种间水平转移中起关键作用。尽管先前的研究表明存在几种MGEs,但尚未对AMR相关的可移动基因组及其相互作用和进化进行全面分析。在本研究中,我们展示了AMR相关的可移动基因组及其在……中的插入热点。整合性接合元件(ICEs)、前噬菌体和串联MGEs位于不同的插入位点,而86%的AMR相关MGEs插入在……和……位点。对四种致病……物种(……、……和……)中……和……位点插入情况的综合分析揭示了不同组的MGEs的存在,包括Tn5252、ICE1108和TnGBS2组ICEs、Φm46.1组前噬菌体、ICE_ICE和ICE_前噬菌体串联MGEs。ICE2603家族的比较ICE基因组学表明,模块交换和获得/缺失是MGEs扩展和进化的主要机制。此外,串联MGEs的观察反映了MGE多样性的一种新机制。而且,一项……竞争试验表明,在不同携带MGEs的分离株之间未观察到明显的适应性代价,一项接合试验揭示了ICE2603家族ICEs的可转移性。我们的统计进一步表明,……中MGEs的流行率和多样性远高于其他三个物种,这促使我们提出假设,即……可能是其他链球菌的MGEs储存库。总之,我们的结果表明,MGEs的获得不仅赋予了……作为多重耐药病原体的能力,而且代表了研究MGEs模块化进化和套娃现象的一个范例。