Department of Bacteriology and Immunology, University of Helsinki, Finland.
Humanitas University, Milano, Italy.
FEBS Lett. 2020 Aug;594(16):2570-2585. doi: 10.1002/1873-3468.13872. Epub 2020 Aug 19.
Streptococci are a broad group of Gram-positive bacteria. This genus includes various human pathogens causing significant morbidity and mortality. Two of the most important human pathogens are Streptococcus pneumoniae (pneumococcus) and Streptococcus pyogenes (group A streptococcus or GAS). Streptococcal pathogens have evolved to express virulence factors that enable them to evade complement-mediated attack. These include factor H-binding M (S. pyogenes) and pneumococcal surface protein C (PspC) (S. pneumoniae) proteins. In addition, S. pyogenes and S. pneumoniae express cytolysins (streptolysin and pneumolysin), which are able to destroy host cells. Sometimes, the interplay between streptococci, the complement, and antistreptococcal immunity may lead to an excessive inflammatory response or autoimmune disease. Understanding the fundamental role of the complement system in microbial clearance and the bacterial escape mechanisms is of paramount importance for understanding microbial virulence, in general, and, the conversion of commensals to pathogens, more specifically. Such insights may help to identify novel antibiotic and vaccine targets in bacterial pathogens to counter their growing resistance to commonly used antibiotics.
链球菌是一组广泛的革兰氏阳性细菌。该属包括各种引起重大发病率和死亡率的人类病原体。两种最重要的人类病原体是肺炎链球菌（肺炎球菌）和化脓性链球菌（A 组链球菌或 GAS）。链球菌病原体已经进化出表达毒力因子的能力，使它们能够逃避补体介导的攻击。其中包括因子 H 结合蛋白 M（化脓性链球菌）和肺炎球菌表面蛋白 C（肺炎链球菌）蛋白。此外，化脓性链球菌和肺炎链球菌表达细胞溶解素（链球菌溶血素和肺炎球菌溶血素），能够破坏宿主细胞。有时，链球菌、补体和抗链球菌免疫之间的相互作用可能导致过度的炎症反应或自身免疫性疾病。了解补体系统在微生物清除和细菌逃逸机制中的基本作用对于理解微生物的毒力至关重要，更具体地说，对于理解从共生菌到病原体的转化至关重要。这些见解可能有助于确定细菌病原体中新的抗生素和疫苗靶点，以对抗它们对常用抗生素日益增长的耐药性。
