AQUAVETAQUAVET, Laboratory of Aquatic Animal Diseases, Veterinary School, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901, Brazil.
IFC, Federal Institute of Santa Catarina, Camboriú, Santa Catarina, 88020-300, Brazil.
Braz J Microbiol. 2022 Dec;53(4):2263-2272. doi: 10.1007/s42770-022-00856-5. Epub 2022 Oct 29.
The weissellosis agent bacterium (WS08 = CBMAI 2730) was isolated from diseased rainbow trout (Oncorhynchus mykiss) in Brazil. The whole genome sequence of this strain was compared with the Mexican W-1 strain, also isolated from diseased rainbow trout, and with the Weissella ceti type strain CECT 7719 (= 1119-1A-09 = CCUG 59653), recovered from the beaked whale. Digital DNA-DNA hybridization pairwise analyses scored 98.7% between the Mexican W-1 and Brazilian WS08 but just 24.4% for both fish isolates compared to the W. ceti type strain CECT 7719. The 16S rRNA gene sequence comparisons with isolates of W. ceti, available at GenBank, were conducted. All rainbow trout-pathogenic isolates grouped close (97% bootstrap confirmation), but when this group was compared to the W. ceti type strain CECT 7719 the similarity varied from 78.9 to 79.1%. Phenotypic assays were also conducted, and the W. ceti type strain diverged from WS08 and W-1 in the hydrolysis of aesculin, D-mannose, and potassium gluconate and in the hydrolysis of hippurate. Moreover, WS08 and W-1 showed weak growth at 5 °C whereas no growth was observed for W. ceti CECT 7719. The major fatty acids (> 10% total fatty acids) presented by WS08 and W-1 were summed feature 8 (C ω7c/C ω6c), summed feature 3 (C ω6c/Cω7c), and C. The results of phylogenetic and phenotypic analyses clearly differentiated the W. ceti CECT 7719 type strain from the assessed pathogenic strains obtained from rainbow trout. Therefore, Weissella strains isolated from rainbow trout, here represented by strain WS08 (= CBMAI 2730), should be known as members of a novel species for which the name Weissella tructae sp. nov. is proposed.
从巴西患病虹鳟鱼（Oncorhynchus mykiss）中分离出 Weissellosis 病原体细菌（WS08 = CBMAI 2730）。该菌株的全基因组序列与墨西哥 W-1 菌株进行了比较，该菌株也从患病虹鳟鱼中分离出来，与从喙鲸中分离出的 Weissella ceti 模式株 CECT 7719（= 1119-1A-09 = CCUG 59653）进行了比较。数字 DNA-DNA 杂交成对分析显示，墨西哥 W-1 株与巴西 WS08 株之间的相似度为 98.7%，而这两个鱼类分离株与 Weissella ceti 模式株 CECT 7719 的相似度仅为 24.4%。对 GenBank 中可用的 Weissella ceti 分离株的 16S rRNA 基因序列进行了比较。所有与虹鳟鱼相关的分离株都紧密聚集（97% 自举确认），但当将该组与 Weissella ceti 模式株 CECT 7719 进行比较时，其相似性从 78.9%到 79.1%不等。还进行了表型分析，Weissella ceti 模式株与 WS08 和 W-1 在 aesculin、D-甘露糖和葡萄糖酸钾的水解以及 hippurate 的水解方面存在差异。此外，WS08 和 W-1 在 5°C 时的生长较弱，而 Weissella ceti CECT 7719 则没有生长。WS08 和 W-1 中存在的主要脂肪酸（占总脂肪酸的>10%）是 summed feature 8（C ω7c/C ω6c）、summed feature 3（C ω6c/C ω7c）和 C。系统发育和表型分析的结果清楚地区分了 Weissella ceti CECT 7719 模式株与从虹鳟鱼中获得的评估致病性菌株。因此，从虹鳟鱼中分离出的 Weissella 菌株，这里以 WS08 株（= CBMAI 2730）为例，应被视为一个新物种的成员，提议将其命名为 Weissella tructae sp. nov.。
