Gram-positive, spore-forming members of the Bacillus cereus group species complex are widespread in natural environments and display various degrees of pathogenicity. Recently, B. cereus group strain Bacillus mycoides Flugge ATCC 21929 was found to represent a novel lineage within the species complex, sharing a relatively low degree of genomic similarity with all B. cereus group genomes (average nucleotide identity [ANI] < 88). ATCC 21929 has been previously associated with the production of a patented antibiotic, antibiotic 60-6 (i.e., cerexin A); however, the virulence potential and growth characteristics of this lineage have never been assessed. Here, we provide an extensive genomic and phenotypic characterization of ATCC 21929, and we assess its pathogenic potential in vitro. ATCC 21929 most closely resembles Bacillus paramycoides NH24A2^T (ANI and in silico DNA-DNA hybridization values of 86.70 and 34.10%, respectively). Phenotypically, ATCC 21929 does not possess cytochrome c oxidase activity and is able to grow at a range of temperatures between 15 and 43°C and a range of pH between 6 and 9. At 32°C, ATCC 21929 shows weak production of diarrheal enterotoxin hemolysin BL (Hbl) but no production of nonhemolytic enterotoxin (Nhe); at 37°C, neither Hbl nor Nhe is produced. Additionally, at 37°C, ATCC 21929 does not exhibit cytotoxic effects toward HeLa cells. With regard to fatty acid composition, ATCC 21929 has iso-C17:0 present in highest abundance. Based on the characterization provided here, ATCC 21929^T (= PS00077A^T = PS00077B^T = PSU-0922^T = BHP^T) represents a novel effective B. cereus group species, which we propose as effective species “Bacillus clarus.”

中文翻译：

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新型有效蜡样芽孢杆菌群种“克氏芽孢杆菌”以从土壤中分离的抗生素生产菌株 ATCC 21929 为代表

蜡样芽孢杆菌群种复合体的革兰氏阳性孢子形成成员广泛存在于自然环境中，并显示出不同程度的致病性。最近，发现蜡状芽孢杆菌群菌株Bacillus mycoides Flugge ATCC 21929 代表物种复合体中的一个新谱系，与所有蜡状芽孢杆菌具有相对较低的基因组相似度组基因组（平均核苷酸同一性 [ANI] < 88）。ATCC 21929 以前曾与获得专利的抗生素抗生素 60-6（即 cerexin A）的生产有关；然而，从未对该谱系的毒力潜力和生长特征进行过评估。在这里，我们提供了 ATCC 21929 的广泛基因组和表型特征，并在体外评估了其致病潜力。ATCC 21929 最类似于副真菌芽孢杆菌 NH24A2 ^T（ANI 和计算机中DNA-DNA 杂交值分别为 86.70% 和 34.10%）。表型上，ATCC 21929 不具有细胞色素c氧化酶活性，能够在 15 至 43°C 的温度范围和 6 至 9 的 pH 值范围内生长。 在 32°C 下，ATCC 21929 显示腹泻肠毒素溶血素 BL (Hbl) 的产生较弱，但不产生非溶血性肠毒素（Nhe）；在 37°C 时，既不产生 Hbl 也不产生 Nhe。此外，在 37°C 下，ATCC 21929 对 HeLa 细胞没有细胞毒性作用。关于脂肪酸组成，ATCC 21929 的 iso-C17:0 含量最高。根据此处提供的特征，ATCC 21929 ^T (= PS00077A ^T = PS00077B ^T = PSU-0922 ^T = BHP ^T ) 代表一种新的有效蜡状芽孢杆菌属物种，我们建议将其作为有效物种“芽孢杆菌。”