Saif Nehal A, Hashem Yomna A, Amin Heba M, Aziz Ramy K
Department of Microbiology and Immunology, Faculty of Pharmacy, October University for Modern Sciences and Arts (MSA), Giza 12451, Egypt.
Department of Microbiology, Faculty of Pharmacy, The British University in Egypt, El-Sherouk City, Cairo 11837, Egypt.
Microorganisms. 2023 May 11;11(5):1265. doi: 10.3390/microorganisms11051265.
Many gut bacteria degrade polysaccharides, providing nutritional advantages to their hosts. Fucose, a mucin degradation product, was suggested as a communication molecule between the resident microbiota and external pathogens. However, the precise role and variants of the fucose utilization pathway remain to be elucidated. Here, we computationally and experimentally investigated the fucose utilization operon of . While the operon is conserved among genomes, a variant pathway, in which an ABC transporter system replaces the fucose permease gene (), was computationally identified in 50 out of 1058 genomes. Comparative genomics and subsystems analysis results were confirmed by polymerase chain reaction-based screening of 40 human isolates, which indicated the conservation of in 92.5% of the isolates (vs. 7.5% of its suggested alternative, ). The in silico predictions were confirmed by in vitro experiments comparing the growth of strains K12, BL21, and isogenic fucose-utilization K12 mutants. Additionally, and transcripts were quantified in K12 and BL21, after in silico analysis of their expression in 483 public transcriptomes. In conclusion, utilizes fucose by two pathway variants, with measurable transcriptional differences. Future studies will explore this variation's impact on signaling and virulence.
许多肠道细菌可降解多糖，为其宿主提供营养优势。岩藻糖是一种粘蛋白降解产物，被认为是常驻微生物群与外部病原体之间的一种通讯分子。然而，岩藻糖利用途径的确切作用和变体仍有待阐明。在此，我们通过计算和实验研究了[具体对象]的岩藻糖利用操纵子。虽然该操纵子在[具体数量]个基因组中是保守的，但通过计算在1058个基因组中的50个中鉴定出一种变体途径，其中一个ABC转运体系统取代了岩藻糖通透酶基因（[具体基因名称]）。通过基于聚合酶链反应对40株人类[具体菌株类型]分离株进行筛选，证实了比较基因组学和子系统分析结果，结果表明92.5%的分离株中存在[具体基因]（相比之下，其建议替代基因的存在比例为7.5%）。通过比较[具体菌株名称]K12、BL21和同基因岩藻糖利用K12突变体的生长情况的体外实验，证实了计算机模拟预测结果。此外，在对483个公共转录组中[具体基因]和[具体基因]的表达进行计算机模拟分析后，对[具体菌株名称]K12和BL21中的[具体基因]和[具体基因]转录本进行了定量分析。总之，[具体菌株名称]通过两种途径变体利用岩藻糖，存在可测量的转录差异。未来的研究将探索这种变异对信号传导和毒力的影响。
