Department of Microbiology and Immunology, New York Medical College, Valhalla, NY 10595.
Department of Pediatrics, Queen Fabiola Children's University Hospital, and Molecular Bacteriology Laboratory, Université Libre de Bruxelles, Brussels, 1020, Belgium.
Microbiol Spectr. 2018 Sep;6(5). doi: 10.1128/microbiolspec.CPP3-0009-2018.
The clinico-epidemiological features of diseases caused by group A streptococci (GAS) is presented through the lens of the ecology, population genetics, and evolution of the organism. The serological targets of three typing schemes (M, T, SOF) are themselves GAS cell surface proteins that have a myriad of virulence functions and a diverse array of structural forms. Horizontal gene transfer expands the GAS antigenic cell surface repertoire by generating numerous combinations of M, T, and SOF antigens. However, horizontal gene transfer of the serotype determinant genes is not unconstrained, and therein lies a genetic organization that may signify adaptations to a narrow ecological niche, such as the primary tissue reservoirs of the human host. Adaptations may be further shaped by selection pressures such as herd immunity. Understanding the molecular evolution of GAS on multiple levels-short, intermediate, and long term-sheds insight on mechanisms of host-pathogen interactions, the emergence and spread of new clones, rational vaccine design, and public health interventions.
通过对生物体的生态学、种群遗传学和进化的研究，呈现了 A 组链球菌（GAS）引起的疾病的临床流行病学特征。三种分型方案（M、T、SOF）的血清学靶标本身就是 GAS 细胞表面蛋白，具有无数的毒力功能和多样化的结构形式。水平基因转移通过产生大量 M、T 和 SOF 抗原的组合来扩展 GAS 抗原的细胞表面 repertoire。然而，血清型决定基因的水平基因转移并非不受限制，其中存在一种遗传组织，可能表明对狭窄生态位的适应，例如人类宿主的主要组织储库。适应可能进一步受到群体免疫等选择压力的影响。从短期、中期和长期等多个层面理解 GAS 的分子进化，可以深入了解宿主-病原体相互作用、新克隆的出现和传播、合理疫苗设计和公共卫生干预的机制。
