Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy.
Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy.
Environ Pollut. 2018 Jun;237:406-413. doi: 10.1016/j.envpol.2018.02.073. Epub 2018 Mar 15.
Sediment samples from three coastal sites - two beach resorts (Beach 1 and Beach 2 sites) and an area lying between an oil refinery and a river estuary (Estuarine site) - were analyzed for antibiotic- and heavy metal (HM)-resistant enterococci. A total of 123 enterococci, 36 E. faecium, 34 E. casseliflavus, 33 E. hirae, 5 E. faecalis, 3 E. durans, 3 E. gallinarum, and 9 Enterococcus spp, were recovered. Strains resistant to erythromycin, tetracycline and quinupristin/dalfopristin (Q/D) were recovered from all sites, whereas multidrug-resistant isolates were recovered only from "Beach 2" (14%) and "Estuarine" (3.7%). As regards HM resistance, the strains showed a high frequency (68%) of cadmium and/or copper resistance and uniform susceptibility to mercury. The prevalence of cadmium-resistant strains was significantly higher among erythromycin-resistant than among erythromycin-susceptible strains. A significant association between cadmium or copper resistance and Q/D resistance was also observed at "Estuarine" site. The levels of the two HMs in sediment from all sites were fairly low, ranging from 0.070 to 0.126 μg/g, for cadmium and from 1.00 to 7.64 μg/g for copper. Mercury was always undetectable. These findings are consistent with reports that low HM concentrations may contribute to co-selection of antibiotic-resistant bacterial strains, including enterococci.
从三个沿海地点（两个海滩度假胜地[海滩 1 和海滩 2 地点]和一个位于炼油厂和河口之间的区域[河口地点]）采集沉积物样本，分析其中的抗生素和重金属（HM）抗性肠球菌。共回收了 123 株肠球菌，其中 36 株粪肠球菌、34 株屎肠球菌、33 株海氏肠球菌、5 株屎肠球菌、3 株耐久肠球菌、3 株鸡肠球菌和 9 株肠球菌属。所有地点均回收了对红霉素、四环素和奎奴普丁/达福普汀（Q/D）耐药的菌株，而只有“海滩 2”（14%）和“河口”（3.7%）地点回收了多药耐药株。关于 HM 耐药性，这些菌株对镉和/或铜具有较高的耐药频率（68%），且对汞均具有一致的敏感性。红霉素耐药株的镉耐药株的流行率明显高于红霉素敏感株。在河口地点还观察到镉或铜耐药性与 Q/D 耐药性之间存在显著关联。所有地点沉积物中两种 HM 的水平均相当低，镉的范围为 0.070 至 0.126μg/g，铜的范围为 1.00 至 7.64μg/g。汞始终无法检测到。这些发现与低 HM 浓度可能有助于包括肠球菌在内的抗生素耐药细菌菌株的共同选择的报告一致。
