Comparative Genomic Analysis of the ICESa2603 Family ICEs and Spread of erm(B)- and tet(O)-Carrying Transferable 89K-Subtype ICEs in Swine and Bovine Isolates in China.
Comparative Genomic Analysis of the ICESa2603 Family ICEs and Spread of erm(B)- and tet(O)-Carrying Transferable 89K-Subtype ICEs in Swine and Bovine Isolates in China.
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ICESa2603 家族 ICE 的比较基因组分析以及中国猪和牛分离株中携带 erm(B) 和 tet(O) 的可转移 89K 亚型 ICE 的传播
DOI：
10.3389/fmicb.2016.00055
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发表时间：
2016
影响因子：
5.2
通讯作者：
Wang L
中科院分区：
文献类型：
--
作者：
Huang J;Liang Y;Guo D;Shang K;Ge L;Kashif J;Wang L
ICESa2603家族的整合和结合元件(ICES)已经从几种链球菌中分离出来；然而，对这些ICE的比较基因组和进化分析目前还处于初级阶段。通过对ICESa2603家族的13个ICE和来自不同寄主和不同位置的两个类似ICESa2603家族的ICE的研究，我们确定ICE由30个相同的同线核心基因和辅助基因组成，这些基因被限制在核心基因的非保守域的基因间位点或3‘端，以维持其功能。ICESa2603家族整合酶IntICESa2603在rplL的3‘端特异性识别一个15bp的att序列(TTATTTAAGAGTAAC)，该序列在链球菌属中高度保守。系统发育分析表明，ICESa2603家族广泛的重组/插入和杂交/镶嵌的发生是ICE多样性显著增加的原因，从而扩大了其寄主范围。在检测的猪链球菌和无乳链球菌中，分别有约42.5%和38.1%的菌株含有ICESa2603家族IV型分泌系统(T4SS)基因，80.5%和62.5%的菌株还携带有ICESa2603基因，表明ICESa2603家族在这些细菌中分布广泛。对新的ST303型猪链球菌临床分离株HB1011进行测序和接合转移，证明89K亚型ICESsuHB1011保留了其可转移的功能，从而使其对四环素和大环内酯类药物产生耐药性。
Integrative and conjugative elements (ICEs) of the ICESa2603 family have been isolated from several species of Streptococcus spp.; however, the comparative genomic and evolutionary analyses of these particular ICEs are currently only at their initial stages. By investigating 13 ICEs of the ICESa2603 family and two ICESa2603 family-like ICEs derived from diverse hosts and locations, we have determined that ICEs comprised a backbone of 30 identical syntenic core genes and accessory genes that were restricted to the intergenic sites or the 3′-end of the non-conserved domain of core genes to maintain its function. ICESa2603 family integrase IntICESa2603 specifically recognized a 15-bp att sequence (TTATTTAAGAGTAAC) at the 3′-end of rplL, which was highly conserved in genus Streptococcus. Phylogenetic analyses suggest that extensive recombination/insertion and the occurrence of a hybrid/mosaic in the ICESa2603 family were responsible for the significant increase in ICE diversity, thereby broadening its host range. Approximately 42.5 and 38.1% of the tested Streptococcus suis and Streptococcus agalactiae clinical isolates respectively contained ICESa2603 family Type IV secretion system (T4SS) genes, and 80.5 and 62.5% of which also respectively carried intICESa2603, indicating that ICESa2603 family is widely distributed across these bacteria. Sequencing and conjugation transfer of a novel sequence type ST303 clinical S. suis isolate HB1011 demonstrated that the 89K-subtype ICESsuHB1011 retained its transferrable function, thereby conferring tetracycline and macrolide resistance.