Trościańczyk Aleksandra, Nowakiewicz Aneta, Tracz Anna Magdalena, Bochniarz Mariola
Sub-Department of Veterinary Microbiology, Department of Preclinical Veterinary Sciences, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033, Lublin, Poland.
Microb Pathog. 2025 May;202:107432. doi: 10.1016/j.micpath.2025.107432. Epub 2025 Feb 26.
The aim of the study was to assess the activity and genetic background of bacteriocins of E. faecium and E. faecalis isolated from different hosts against methicillin-resistant Staphylococcus aureus (MRSA), E. faecium and E. faecalis with vancomycin (VRE) and high-level aminoglycoside (HLAR) resistance, Streptococcus agalactiae, and Listeria monocytogenes. The research was carried out using qualitative method and partially purified bacteriocins. The occurrence of 12 bacteriocin genes was examined and their sequences were analysed. Bacteriocins showing inhibitory activity against indicator strains were isolated from 95 % of E. faecium and 50 % of E. faecalis gave positive results in qualitative method. The highest inhibitory activity of bacteriocins isolated from E. faecium was obtained against E. faecium (100-25600AU/ml), E. faecalis VRE/HLAR (100-12800AU/ml), and L. monocytogenes (100-6400AU/ml), while bacteriocins isolated from E. faecalis were active against L. monocytogenes (100-25600AU/ml). The lowest activity of bacteriocins isolated from both Enterococcus species was determined against S. agalactiae (100AU/ml) and MRSA (100-800AU/ml). The presence of at least one bacteriocin gene was detected in 95 % of E. faecium and 52 % of E. faecalis. Four genes encoding bacteriocins was found (entB, enxAB, entA, entP), with the highest frequency of entA (97 %) in E. faecium and entB (53 %) in E. faecalis. The changes observed in the nucleotides among the entA, entB, and enxAB genes did not affect the activity of the bacteriocins. To sum up, E. faecium and E. faecalis may be a source of bacteriocins inhibiting the growth of drug-resistant bacteria, such as MRSA, HLAR, VRE, and L. monocytogenes.
本研究旨在评估从不同宿主分离出的屎肠球菌和粪肠球菌的细菌素对耐甲氧西林金黄色葡萄球菌（MRSA）、耐万古霉素（VRE）和高水平氨基糖苷类（HLAR）的屎肠球菌和粪肠球菌、无乳链球菌和单核细胞增生李斯特菌的活性及遗传背景。该研究采用定性方法和部分纯化的细菌素进行。检测了12种细菌素基因的存在情况并分析了其序列。在定性方法中，从95%的屎肠球菌和50%的粪肠球菌中分离出的对指示菌株具有抑制活性的细菌素呈阳性结果。从屎肠球菌分离出的细菌素对屎肠球菌（100 - 25600AU/ml）、耐万古霉素/高水平氨基糖苷类的粪肠球菌（100 - 12800AU/ml）和单核细胞增生李斯特菌（100 - 6400AU/ml）具有最高抑制活性，而从粪肠球菌分离出的细菌素对单核细胞增生李斯特菌（100 - 25600AU/ml）有活性。从两种肠球菌分离出的细菌素对无乳链球菌（100AU/ml）和MRSA（100 - 800AU/ml）的活性最低。在95%的屎肠球菌和52%的粪肠球菌中检测到至少一种细菌素基因。发现了四个编码细菌素的基因（entB、enxAB、entA、entP），其中entA在屎肠球菌中的频率最高（97%），entB在粪肠球菌中的频率最高（53%）。在entA、entB和enxAB基因中观察到核苷酸的变化并未影响细菌素的活性。综上所述，屎肠球菌和粪肠球菌可能是抑制耐药细菌生长的细菌素来源，如MRSA、HLAR、VRE和单核细胞增生李斯特菌。
