College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, China.
Technology and Research Center of Gansu Province for Embryonic Engineering of Bovine and Sheep & Goat, Lanzhou, Gansu, China.
Sci Rep. 2024 Jun 6;14(1):13010. doi: 10.1038/s41598-024-63418-9.
Studies on Bdellovibrio and like organisms (BALOs), obligate predatory bacteria, have highlighted the possibility of regulating bacteria and biofilms; however, yak-derived BALOs are yet to be reported. We aimed to characterize the BALOs isolated and identified from yak (Bos grunniens) feces and examine application potential. BALOs were isolated from healthy yak fecal samples, with Escherichia coli (ATCC 25922) as prey using the double-layer agar method, identified by transmission electron microscopy (TEM), and the specific 16S rDNA sequencing analysis. Sequencing of the 16S rDNA gene indicated that this isolate was 91% similar to the Bdellovibrio sp. NC01 reference strain and was named YBD-1. Proportion of YBD-1 lysed bacteria is 12/13. The YBD-1 showed best growth at 25-40°C, 0-0.25% (w/v) NaCl, and pH 6.5-7.5. YBD-1 significantly reduced the planktonic cells and biofilms of E.coli in co-culture compared to the E.coli group. Additionally, SEM analysis indicated that YBD-1 significantly reduced biofilm formation in E. coli. Furthermore, quantitative Real Time-polymerase chain reaction (qRT-PCR) showed that the expression of the virulence genes fim and iroN and the genes pgaABC involved in biofilm formation went down significantly. We concluded that YBD-1 may have the potential to control bacterial growth and biofilm-associated bacterial illnesses.
关于蛭弧菌和类似生物（BALOs）的研究，这些专性捕食性细菌使调控细菌和生物膜成为可能；然而，尚未有关于牦牛来源的 BALOs 的报道。我们旨在从牦牛（Bos grunniens）粪便中分离和鉴定 BALOs，并研究其应用潜力。我们采用双层琼脂法，以大肠杆菌（ATCC 25922）为猎物，从健康牦牛粪便样本中分离 BALOs，利用透射电子显微镜（TEM）进行鉴定，并进行特定的 16S rDNA 测序分析。16S rDNA 基因测序表明，该分离株与 Bdellovibrio sp. NC01 参考株的相似度为 91%，并将其命名为 YBD-1。YBD-1 裂解细菌的比例为 12/13。YBD-1 在 25-40°C、0-0.25%（w/v）NaCl 和 pH 6.5-7.5 条件下生长最好。与大肠杆菌组相比，YBD-1 在共培养中显著减少了浮游细胞和生物膜中的大肠杆菌数量。此外，SEM 分析表明，YBD-1 显著减少了大肠杆菌生物膜的形成。此外，定量实时聚合酶链反应（qRT-PCR）显示，毒力基因 fim 和 iroN 以及参与生物膜形成的基因 pgaABC 的表达显著下降。我们得出结论，YBD-1 可能具有控制细菌生长和生物膜相关细菌病的潜力。
