Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil.
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil.
Environ Pollut. 2021 Nov 1;288:117804. doi: 10.1016/j.envpol.2021.117804. Epub 2021 Jul 17.
In soils, the presence of clinically relevant bacteria carrying ARGs, including extended-spectrum β-lactamase- and plasmid-mediated AmpC β-lactamase-encoding genes, is an underestimated public health problem that requires more attention. For this investigation, 300 samples from agricultural and non-agricultural soils were used to obtain 41 MDR E. coli isolates, standing out the resistance to β-lactams, fluoroquinolones and colistin. Virulence genes related to diarrheagenic E. coli and extraintestinal pathogenic E. coli were detected. Several ARGs were found, highlighting the presence of at least one β-lactamase-encoding gene (bla, bla, bla, bla, bla, and/or bla) in each isolate. Among the fluoroquinolone-resistant E. coli isolates, the plasmid-mediated quinolone resistance genes (qnrB and oqxA) and substitutions in the quinolone resistance-determining regions were detected. Some isolates were resistant to colistin (MICs of 4-8 mg/L) and, although no mcr-like gene was detected, substitutions in the two-component systems involving PhoP/PhoQ and PmrA/PmrB were found. Furthermore, the E. coli isolates presented plasmids and class 1 integrons, the last one detected in all isolates. The ARGs bla, aadA and dfrA and the lpfA virulence-associated gene presented statistically significant differences (P < 0.05) in agricultural soils, while the bla gene presented a statistically significant difference in non-agricultural soils. Thirty-eight sequence types (STs) were identified among the isolates, spotlighting the 20 different STs that carried bla and bla genes and those commonly reported in infections worldwide. The occurrence of virulent, multidrug- and colistin-resistant E. coli isolates in soils could lead to contamination of surrounding environments and food, increasing the risk of human and animal exposure. Therefore, this study contributes to a better understanding of E. coli in soils and reinforces the importance of the One Health approach to antimicrobial resistance surveillance.
在土壤中，存在临床相关的携带 ARG 的细菌，包括超广谱β-内酰胺酶和质粒介导的 AmpC β-内酰胺酶编码基因，这是一个被低估的公共卫生问题，需要引起更多关注。在这项调查中，从农业和非农业土壤中采集了 300 个样本，获得了 41 株多药耐药大肠杆菌分离株，这些分离株对β-内酰胺类、氟喹诺酮类和多粘菌素表现出耐药性。检测到与致腹泻大肠杆菌和肠外致病性大肠杆菌相关的毒力基因。发现了几种 ARG，每个分离株至少存在一种β-内酰胺酶编码基因（bla、bla、bla、bla、bla 和/或 bla）。在氟喹诺酮类耐药大肠杆菌分离株中，检测到质粒介导的喹诺酮类耐药基因（qnrB 和 oqxA）和喹诺酮类耐药决定区的取代。一些分离株对多粘菌素耐药（MIC 为 4-8mg/L），虽然没有检测到 mcr 样基因，但发现了涉及 PhoP/PhoQ 和 PmrA/PmrB 的两个组件系统的取代。此外，大肠杆菌分离株携带质粒和 1 类整合子，最后一个在所有分离株中均有发现。bla、aadA 和 dfrA 基因和 lpfA 毒力相关基因在农业土壤中存在统计学显著差异（P<0.05），而 bla 基因在非农业土壤中存在统计学显著差异。在分离株中鉴定出 38 种序列型（ST），其中 20 种不同的 ST 携带 bla 和 bla 基因，这些基因在全球感染中普遍存在。在土壤中存在毒力、多药和多粘菌素耐药大肠杆菌分离株可能导致周围环境和食物的污染，增加人类和动物暴露的风险。因此，本研究有助于更好地了解土壤中的大肠杆菌，并加强了对动物健康的重视。
