School of Medical Science, and Menzies Health Institute Queensland, Griffith University, Parklands, QLD, Australia.
School of Dentistry and Oral Health, and Menzies Health Institute Queensland, Griffith University, Parklands, QLD, Australia.
ISME J. 2021 Jul;15(7):2158-2162. doi: 10.1038/s41396-021-00934-w. Epub 2021 Mar 1.
In bacteria, guaA encodes guanosine monophosphate synthetase that confers an ability to biosynthesize guanine nucleotides de novo. This enables bacterial colonization in different environments and, while guaA is widely distributed among Bacteroidetes and Firmicutes, its contribution to the inhabitation of the human microbiome by commensal bacteria is unclear. We studied Streptococcus as a commensal urogenital tract bacterium and opportunistic pathogen, and explored the role of guaA in bacterial survival and colonization of urine. Analysis of guaA-deficient Streptococcus revealed guanine utilization is essential for bacterial colonization of this niche. The genomic location of guaA in other commensals of the human urogenital tract revealed substantial cross-phyla diversity and organizational structures of guaA that are divergent across phyla. Essentiality of guaA for Streptococcus colonization in the urinary tract establishes that purine biosynthesis is a critical element of the ability of this bacterium to survive and colonize in the host as part of the resident human microbiome.
在细菌中，guaA 编码鸟苷酸单磷酸合酶，使其能够从头生物合成鸟苷酸核苷酸。这使细菌能够在不同的环境中定殖，尽管 guaA 在拟杆菌门和厚壁菌门中广泛分布，但它对共生菌栖息在人类微生物组中的贡献尚不清楚。我们以尿生殖道共生菌和机会性病原体链球菌作为研究对象，探索了 guaA 在细菌存活和尿液定殖中的作用。对guaA 缺陷型链球菌的分析表明，嘌呤的利用对该菌在该小生境中的定殖是必不可少的。人类尿生殖道其他共生菌中 guaA 的基因组位置揭示了跨门的广泛多样性和 guaA 的组织结构在门之间存在差异。guaA 对链球菌在尿路定殖的必需性表明，嘌呤生物合成是该菌作为常驻人类微生物组的一部分在宿主中存活和定殖的能力的关键因素。
