摘要

       河流沉积物被认为是细菌密度和活动的热点。此外，已知高细菌密度和生物膜形成促进水平基因转移，后者在抗菌素耐药性的传播中起着至关重要的作用。因此可以假设沉积物是抗生素抗性细菌 (ARB) 和抗性基因 (ARG) 的储存库，特别是在从处理过的污水中接收微生物和药物残留的河流中。我们分析了 782 株大肠杆菌对 24 种抗菌剂的表型敏感性，并测量了小溪水和沉积物提取物中五种 ARG 的相对丰度。与在溪水中发现的大肠杆菌相比，我们没有发现从沉积物中分离出的抗性大肠杆菌比例普遍增加的证据。对于大多数抗微生物药物，在水和沉积物中检测到耐药分离株的可能性相似，或者在后一个隔间中检测到的可能性更低。在沉积物传播的样品中，ARG 的平均相对丰度适度增加。一般来说，由于细菌密度较高，沉积物中抗性细胞和抗性基因的绝对丰度超过了远洋水平。因此，河底代表了一个 ARB 和 ARG 的水库，可以通过再悬浮来动员。

       River sediment is considered a hot spot for bacterial density and activity. In addition, it is known that high bacterial density and biofilm formation promote horizontal gene transfer, which plays a crucial role in the spread of antimicrobial resistance. It can therefore be assumed that the sediment is a reservoir of antibiotic-resistant bacteria (ARB) and resistance genes (ARG), especially in rivers that receive microorganisms and drug residues from treated sewage. We analyzed the phenotypic sensitivity of 782 strains of E. coli to 24 antibacterial agents, and measured the relative abundance of five ARGs in stream water and sediment extracts. Compared with the Escherichia coli found in streams, we did not find evidence that the proportion of resistant Escherichia coli isolated from sediments has generally increased. For most antimicrobial drugs, the likelihood of detecting resistant isolates in water and sediment is similar, or less likely to be detected in the latter compartment. In sediment-spread samples, the average relative abundance of ARG increased moderately. Generally speaking, due to the high density of bacteria, the absolute abundance of resistant cells and resistance genes in the sediment exceeds the pelagic level. Therefore, the bottom of the river represents a reservoir of ARB and ARG, which can be mobilized by resuspension.

https://academic.oup.com/femsec/article/94/9/fiy128/5047301?login=true