Lv Chao, Abdullah Mohd, Chen Weiye, Zhou Nan, Cheng Zile, Chen Yiwen, Li Min, Simpson Kenneth W, Elsaadi Ahmed, Zhu Yongzhang, Lipkin Steven M, Chang Yung-Fu
bioRxiv. 2024 Jun 17:2024.06.16.599199. doi: 10.1101/2024.06.16.599199.
The strain harboring the polyketide synthase island encodes the genotoxin colibactin, a secondary metabolite reported to have severe implications for human health and for the progression of colorectal cancer. The present study involved whole-genome-wide comparison and phylogenetic analysis of harboring isolates to gain insight into the distribution and evolution of these organism. Fifteen strains isolated from patients with ulcerative colitis were sequenced, 13 of which harbored pks islands. In addition, 2,654 genomes from the public database were also screened for harboring genomes, 158 of which were -positive isolates. Whole-genome-wide comparison and phylogenetic analysis revealed that 171 (158+13) -positive isolates belonged to phylogroup B2, and most of the isolates associated to sequence types ST73 and ST95. One isolate from an ulcerative colitis (UC) patient was of the sequence type ST8303. The maximum likelihood tree based on the core genome of -positive isolates revealed horizontal gene transfer across sequence types and serotypes. Virulome and resistome analyses revealed the preponderance of virulence genes and a reduced number of antimicrobial genes in -positive isolates. This study strongly contributes to understanding the evolution of islands in .
携带聚酮合酶岛的菌株编码基因毒素大肠杆菌素，这是一种据报道对人类健康和结直肠癌进展有严重影响的次级代谢产物。本研究对携带该菌株的分离株进行了全基因组比较和系统发育分析，以深入了解这些生物体的分布和进化情况。对从溃疡性结肠炎患者中分离出的15株菌株进行了测序，其中13株携带pks岛。此外，还从公共数据库中筛选了2654个基因组以寻找携带该菌株的基因组，其中158个为阳性分离株。全基因组比较和系统发育分析表明，171株（158 + 13）阳性分离株属于B2系统发育群，并且大多数分离株与序列类型ST73和ST95相关。一名溃疡性结肠炎（UC）患者的分离株序列类型为ST8303。基于阳性分离株核心基因组的最大似然树揭示了跨序列类型和血清型的水平基因转移。毒力组和耐药组分析显示，阳性分离株中毒力基因占优势，抗菌基因数量减少。本研究为理解大肠杆菌中pks岛的进化做出了重要贡献。
