Departamento de Veterinária, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570 900, Brazil.
Probiotics Antimicrob Proteins. 2017 Jun;9(2):157-162. doi: 10.1007/s12602-017-9263-0.
Corynebacterium vitaeruminis MRU4 was isolated from the cow rumen and was differentiated from other isolates by rep-PCR and RAPD and identified by 16S rRNA sequencing. This strain presented higher survival rates for low pH and bile salts treatments, and it was able to survive and multiply in simulated gastric and intestinal environments. C. vitaeruminis MRU4 had a 53.2% auto-aggregation rate, 42.4% co-aggregation rate with Listeria monocytogenes Scott A, 41.6% co-aggregation rate with Enterococcus faecalis ATCC 19443, 10.0% co-aggregation rate with Lactobacillus sakei ATCC 15521, and 98.2% cell surface hydrophobicity rate. PCR analysis showed the presence of EFTu and map genes. The strain possessed positive results for deconjugation of bile salts (taurocholic acid, taurodeoxycholic acid, glycocholic acid, and glycodeoxycholic acid) and positive results for β-galactosidase activity and lactose assimilation activity (glucose of 8.15 ± 0.01 CFU/ml and lactose of 9.24 ± 0.02 CFU/ml). No virulence was observed by phenotypical tests. C. vitaeruminis MRU4 was resistant to oxacillin, gentamicin, erythromycin, clindamycin, sulfa/trimethoprim, and rifampicin by the disc diffusion method and showed resistance just for vancomycin by the Etest® strips test. The strain was negative for 50 tested virulence and resistance genes based on performed PCR. Based on our knowledge, this is the first report regarding the beneficial potential of one C. vitaeruminis strain.
从奶牛瘤胃中分离出棒状杆菌属 vitaeruminis MRU4，通过 rep-PCR 和 RAPD 将其与其他分离株区分开来，并通过 16S rRNA 测序进行鉴定。该菌株在低 pH 值和胆汁盐处理下具有更高的存活率，并且能够在模拟的胃和肠道环境中存活和繁殖。C. vitaeruminis MRU4 的自动聚集率为 53.2%，与单核细胞增生李斯特菌 Scott A 的共聚集率为 42.4%，与粪肠球菌 ATCC 19443 的共聚集率为 41.6%，与乳杆菌 sakei ATCC 15521 的共聚集率为 10.0%，细胞表面疏水性率为 98.2%。PCR 分析显示存在 EFTu 和 map 基因。该菌株具有胆汁盐去共轭（牛胆酸、牛脱氧胆酸、甘胆酸和甘脱氧胆酸）的阳性结果，以及β-半乳糖苷酶活性和乳糖同化活性的阳性结果（葡萄糖为 8.15±0.01 CFU/ml，乳糖为 9.24±0.02 CFU/ml）。表型试验未观察到毒力。C. vitaeruminis MRU4 对苯唑西林、庆大霉素、红霉素、克林霉素、磺胺/甲氧苄啶和利福平的药敏纸片扩散法耐药，而 Etest®条法仅对万古霉素耐药。根据 PCR 结果，该菌株对 50 种测试的毒力和耐药基因均为阴性。据我们所知，这是首次报道一株棒状杆菌属 vitaeruminis 菌株具有有益潜力。
