SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, South Africa.
Applied and Environmental Microbiology Research Group (AEMREG), University of Fort Hare, Alice 5700, South Africa.
Int J Mol Sci. 2023 Feb 3;24(3):2993. doi: 10.3390/ijms24032993.
Enterococci are regarded as a better indication of faecal pollution in freshwater and marine waters. Their levels in seawater are positively connected with swimming-related gastrointestinal disorders. This study used an -specific polymerase chain reaction (PCR) to characterize the isolates. Classes 1 and 2 integrons were examined for environmental isolates using a standard biological procedure. All strains were assessed against a panel of 12 antibiotics from various classes using disc diffusion methods. The microdilution method was used to work out the minimum inhibitory concentration (MIC) according to the CLSI guiding principles. The combination therapy of the resistant drugs was evaluated using a checkerboard assay and a time-dependent test for assessing their bactericidal or bacteriostatic activity. The gene diversity of the tested organisms was analyzed with the aid of Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR. In total, 57 spp. environmental samples were recovered, in which (33.33%) and (59.65%) were the dominant species. Resistance to linezolid, ciprofloxacin, erythromycin, gentamicin, vancomycin, rifampicin, and tetracycline was prevalent. Fifty (50) strains tested positive for class 1 integron, more frequent in and isolates, with no gene cassette array discovered. A combination of gentamicin (MIC 4 µg/mL) with vancomycin (MIC 256 µg/mL) antibiotics against showed antibacterial activity. In contrast, the combination of ciprofloxacin (1 µg/mL) with Ampicillin (16 µg/mL) antibiotics against showed a bacteriostatic effect. The ERIC-PCR analysis pointed out that most of the assessed isolates have close genetic similarities.
肠球菌被认为是淡水和海水中粪便污染的更好指示物。它们在海水中的水平与与游泳相关的胃肠道疾病呈正相关。本研究使用特定的聚合酶链反应（PCR）来对分离物进行特征分析。使用标准生物学程序检查了环境分离物的 1 类和 2 类整合子。使用圆盘扩散法对所有菌株进行了来自不同类别的 12 种抗生素的药敏试验。根据 CLSI 指导原则，使用微量稀释法测定最小抑菌浓度（MIC）。使用棋盘试验和时间依赖性试验评估耐药药物的联合治疗，以评估其杀菌或抑菌活性。借助肠杆菌重复基因间一致序列（ERIC）PCR 分析了测试生物的基因多样性。总共回收了 57 株环境 spp. 分离物，其中 （33.33%）和 （59.65%）是优势种。对利奈唑胺、环丙沙星、红霉素、庆大霉素、万古霉素、利福平、和四环素耐药较为普遍。50 株（50%）菌株检测到 1 类整合子阳性，在 和 分离物中更为常见，未发现基因盒阵列。庆大霉素（MIC 4 µg/mL）与万古霉素（MIC 256 µg/mL）联合对 表现出抗菌活性。相比之下，环丙沙星（1 µg/mL）与氨苄西林（16 µg/mL）联合对 表现出抑菌作用。ERIC-PCR 分析表明，评估的大多数分离物具有密切的遗传相似性。
