Helicobacter kumamotonensis sp. nov., isolated from human clinical specimens
Helicobacter kumamotonensis sp. nov., isolated from human clinical specimens
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DOI：
10.1099/ijsem.0.005732
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发表时间：
2023-01-01
影响因子：
2.8
通讯作者：
Sawa，Tomohiro
中科院分区：
文献类型：
--
作者：
Kawamura，Yoshiaki;Fujimoto，Yuko;Sawa，Tomohiro
从患有弥漫性大 B 细胞淋巴瘤的患者的血液中分离出革兰氏染色阴性螺旋细菌 (PAGU 1991T)。基于16S rRNA基因序列的系统发育分析表明，该分离株与Helicobacter equorumLMG 23362T密切相关（99.1%相似性），最初是从健康马的粪便样本中分离出来的。 PAGU 1991T 与我们菌株库中的 PAGU 1750 (= CCUG 41437) 也非常密切相关，相似度为 99.7 %。基于 23S rRNA 基因序列和 GyrA 氨基酸序列的其他系统发育分析进一步支持了两种人类分离株（PAGU 1991T 和 PAGU 1750）与马品系之间的密切关系。然而，基于 16S rRNA 的系统发育分析表明，这两个人类分离株形成了与马品系不同的谱系（相似性低于 99.2 %）。在基于数字 DNA-DNA 杂交的硅牛基因组比较中，基于母细胞的平均核苷酸同一性和使用两个人类分离株和幽门螺杆菌模式株之间的研究的直系同源平均核苷酸同一性。 equorum 显示的值分别小于 52.40、93.47 和 93.50%，而两个人类分离株之间的值分别为 75.8、97.2 和 97.2%。这些数据清楚地表明，这两种人类分离株形成了一个物种，与幽门螺旋杆菌不同。法定人数。在形态学上，人类分离株可以通过鞭毛的类型来区分。人类分离株显示出双极鞘鞭毛，而 H.群体是单极的。从生物化学角度来看，人类分离株的特征是在 42°C 微需氧条件下生长且无法还原硝酸盐。我们得出的结论是，从地理和时间上不同的来源获得的两种人类分离株是一个新物种，我们建议将其命名为熊本螺杆菌。 11月，模式菌株PAGU 1991T(=GTC 16810T=CCUG 75774T)。
A Gram-stain-negative, spiral bacterium (PAGU 1991T) was isolated from the blood of a patient with diffuse large B-cell lymphoma. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate was very closely related toHelicobacter equorumLMG 23362T(99.1 % similarity), originally isolated from a faecal sample from a healthy horse. PAGU 1991Twas also very closely related to PAGU 1750 in our strain library (=CCUG 41437) with 99.7 % similarity. Additional phylogenetic analyses based on the 23S rRNA gene sequence and GyrA amino acid sequence further supported the close relationship between the two human isolates (PAGU 1991Tand PAGU 1750) and the horse strain. However, a phylogenetic analysis based on 16S rRNA showed that the two human isolates formed a lineage that was distinct from the horse strain (less than 99.2 % similarity).In silicowhole-genome comparisons based on digital DNA–DNA hybridization, average nucleotide identity based onblastand orthologous average nucleotide identity usingusearchbetween the two human isolates and the type strain ofH. equorumshowed values of less than 52.40, 93.47, and 93.50 %, respectively, whereas those between the two human isolates were 75.8, 97.2, and 97.2 %, respectively. These data clearly demonstrated that the two human isolates formed a single species, distinct fromH. equorum. Morphologically, the human isolates could be distinguished by the type of flagella; the human isolates showed a bipolar sheathed flagellum, whereas that ofH. equorumwas monopolar. Biochemically, the human isolate was characterized by growth at 42 °C under microaerobic conditions and nitrate reduction unability. We conclude that the two human isolates, obtained from geographically and temporally distinct sources, were a novel species, for which we propose the nameHelicobacter kumamotonensissp. nov., with the type strain PAGU 1991T(=GTC 16810T=CCUG 75774T).