A new perspective on ancient Mitis group streptococcal genetics.
A new perspective on ancient Mitis group streptococcal genetics.
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DOI：
10.1099/mgen.0.000753
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发表时间：
2022-03
影响因子：
3.9
通讯作者：
Bentley SD
中科院分区：
文献类型：
--
作者：
Belman S;Chaguza C;Kumar N;Lo S;Bentley SD
Mitis集团 链球菌 是存在于鼻咽和口腔中的人类专性细菌。它们包括脑膜炎和致病性物种，其中最著名的是肺炎链球菌-脑膜炎和肺炎的主要原因。病原菌和致病菌之间的主要区别是多糖荚膜的存在，多糖荚膜是病原菌的主要毒力因子。 S. pneumoniae，也存在于其他哺乳动物中。我们目前对致病性和致病性物种的进化分歧的理解是从现存菌株推断的。古老的基因组可以进一步阐明链球菌的进化历史。我们从一个有5700年历史的古老宏基因组中提取了链球菌基因组读数，并致力于表征它们。由于链球菌中常见的过度种内和种间重组，我们无法解析单个种。此外，古代宏基因组的复合读数不适合任何特定现存物种的多样性。使用荚膜基因数据库和AT-含量分析，我们确定这个古老的宏基因组缺失了链球菌荚膜形成所必需的多糖合成基因。多种锌金属蛋白酶的存在表明对宿主IgA 1的适应已经开始，并且其他毒力因子的存在进一步暗示了宿主-微生物之间密切相互作用的发展，尽管没有荚膜表明不能引起侵袭性疾病。肺炎球菌溶血素等特异性毒力因子的存在意味着这些基因通过链球菌进化得到稳定维持，这可能会加强它们作为抗肺炎球菌疫苗抗原的价值，同时保持对它们在细菌物种中潜在存在的认识。根据詹森等人的"我们的初步分析为这个长期居住在人类鼻咽部的Mitis群体提供了历史背景 链球菌。
Mitis group Streptococcus are human obligate bacteria residing in the nasopharynx and oral cavity. They comprise both commensal and pathogenic species with the most well-known being Streptococcus pneumoniae – a leading cause of meningitis and pneumonia. A primary difference between the commensal and pathogenic species is the presence of the polysaccharide capsule – a major virulence factor in S. pneumoniae , also present in other commensal species. Our current understanding of the evolutionary divergence of the pathogenic and commensal species has been inferred from extant strains. Ancient genomes can further elucidate streptococcal evolutionary history. We extracted streptococcal genome reads from a 5700-year-old ancient metagenome and worked towards characterizing them. Due to excessive within- and between-species recombination common among streptococci we were unable to parse individual species. Further, the composite reads of the ancient metagenome do not fit within the diversity of any specific extant species. Using a capsular gene database and AT-content analysis we determined that this ancient metagenome is missing polysaccharide synthesis genes integral to streptococcal capsule formation. The presence of multiple zinc metalloproteases suggests that adaptation to host IgA1 had begun and the presence of other virulence factors further implies development of close host–microbe interactions, though the absence of a capsule suggests an inability to cause invasive disease. The presence of specific virulence factors such as pneumolysin implies stable maintenance of such genes through streptococcal evolution that may strengthen their value as anti-pneumococcal vaccine antigens, while maintaining awareness of their potential presence in commensal species. Following from Jensen et al.’s initial analysis we provide historical context for this long time human nasopharyngeal resident, the Mitis group Streptococcus .
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影响因子：
64.8
作者：
Bos KI;Harkins KM;Herbig A;Coscolla M;Weber N;Comas I;Forrest SA;Bryant JM;Harris SR;Schuenemann VJ;Campbell TJ;Majander K;Wilbur AK;Guichon RA;Wolfe Steadman DL;Cook DC;Niemann S;Behr MA;Zumarraga M;Bastida R;Huson D;Nieselt K;Young D;Parkhill J;Buikstra JE;Gagneux S;Stone AC;Krause J
通讯作者：
Krause J
影响因子：
10.7
作者：
Mostowy RJ;Croucher NJ;De Maio N;Chewapreecha C;Salter SJ;Turner P;Aanensen DM;Bentley SD;Didelot X;Fraser C
通讯作者：
Fraser C
影响因子：
6.4
作者：
Bek-Thomsen, Malene;Poulsen, Knud;Kilian, Mogens
通讯作者：
Kilian, Mogens
影响因子：
3.9
作者：
Page AJ;Taylor B;Delaney AJ;Soares J;Seemann T;Keane JA;Harris SR
通讯作者：
Harris SR
影响因子：
6.4
作者：
Kilian, Mogens;Tettelin, Herve
通讯作者：
Tettelin, Herve