Kirchner Miranda J, Loy Daniel, Williamson Susanna, Whatmore Adrian M
Department of Bacteriology, Animal & Plant Health Agency (Weybridge), Woodham Lane, Addlestone, Surrey, UK.
Present address: Astrobiology OU Faculty of Science, Technology, Engineering and Mathematics, The Open University, Milton Keynes, UK.
Int J Syst Evol Microbiol. 2025 May;75(5). doi: 10.1099/ijsem.0.006776.
A Gram-positive coccus-shaped bacterium, which could not be identified by classical determinative bacteriology approaches, was isolated from the liver of two pigs in the United Kingdom. Initial testing based on cellular morphology and biochemical characteristics tentatively assigned the isolates to the genus but did not match any previously described species. The analysis of the 16S rRNA sequence determined that the isolates were most closely related to (98.6% identity). Analysis of three further housekeeping genes frequently applied in streptococcal taxonomy, , and , and a comparison against available type strain sequences confirmed that the isolates were most similar to in all cases (84.3%, 86.9% and 90.2% identity, respectively). The comparison of the average nucleotide identity (ANI) and DNA-DNA hybridization values demonstrated that the novel species was distinct from other streptococcal species. Pairwise ANI values revealed that the two studied strains shared a pairwise ANI of 99.25% but were clearly distinct from previously described species (ANI ≤81.1% - best match ). The taxonomic analysis described confirmed that the two strains represent a novel species for which the name sp. nov. is suggested, with strain 20-1249 (=NCTC 15092=LMG 33498) as the type strain.
从英国的两头猪的肝脏中分离出一种革兰氏阳性球菌，用经典的鉴定细菌学方法无法鉴定该菌。基于细胞形态学和生化特性的初步检测暂时将分离株归为该属，但与之前描述的任何物种都不匹配。16S rRNA序列分析确定分离株与（相似度为98.6%）关系最为密切。对链球菌分类学中常用的另外三个管家基因、和进行分析，并与可用的模式菌株序列进行比较，证实分离株在所有情况下与最为相似（相似度分别为84.3%、86.9%和90.2%）。平均核苷酸同一性（ANI）和DNA-DNA杂交值的比较表明，该新物种与其他链球菌物种不同。成对ANI值显示，两个研究菌株的成对ANI为99.25%，但与之前描述的物种明显不同（ANI≤81.1% - 最佳匹配）。所描述的分类学分析证实，这两个菌株代表一个新的物种，建议将其命名为sp. nov.，菌株20-1249（=NCTC 15092=LMG 33498）作为模式菌株。
