Department of Clinical Analysis, Toxicology and Food Science, School of Pharmaceutical, Sciences of Ribeirão Preto, University of São Paulo (USP), Av. do Café S/N. Monte Alegre, Ribeirão Preto, SP, 14040-903, Brazil.
Environ Monit Assess. 2019 Apr 29;191(5):314. doi: 10.1007/s10661-019-7461-9.
The use of pesticides has been increasing due to the great agricultural production worldwide. The pesticides are used to eradicate pests and weeds; however, these compounds are classified as toxic to non-target organisms. Atrazine and diuron are herbicides widely used to control grassy and broadleaf weeds and weed control in agricultural crops and non-crop areas. Heavy metals are also important environmental contaminants that affect the ecological system. This study aimed to investigate the presence of herbicides-degrading genes and heavy metal resistance genes in bacterial isolates from two different soil samples from two Brazilian regions and to determine the genetic location of these genes. In this study, two isolates were obtained and identified as Escherichia fergusonii and Bacillus sp. Both isolates presented atzA, atzB, atzC, atzD, atzE, atzF, puhA, and copA genes and two plasmids each, being the major with ~ 60 Kb and a smaller with ~ 3.2 Kb. Both isolates presented the atzA-F genes inside the larger plasmid, while the puhA and copA genes were detected in the smaller plasmid. Digestion reactions were performed and showed that the ~ 60-Kb plasmid presented the same restriction profile using different restriction enzymes, suggesting that this plasmid harboring the complete degradation pathway to atrazine was found in both isolates. These results suggest the dispersion of these plasmids and the multi-herbicide degradation potential in both isolates to atrazine and diuron, which are widely used in different culture types worldwide.
由于全球农业生产的巨大需求，农药的使用量一直在增加。这些农药用于消灭害虫和杂草；然而，这些化合物被归类为对非目标生物有毒。莠去津和敌草隆是广泛用于控制草地和阔叶杂草以及农业作物和非作物区杂草控制的除草剂。重金属也是影响生态系统的重要环境污染物。本研究旨在调查来自巴西两个不同地区的两个土壤样本中的细菌分离物中是否存在除草剂降解基因和重金属抗性基因，并确定这些基因的遗传位置。在这项研究中，获得并鉴定了两种分离物，分别为埃希氏菌（Escherichia fergusonii）和芽孢杆菌（Bacillus sp.）。两种分离物均携带atzA、atzB、atzC、atzD、atzE、atzF、puhA 和 copA 基因，每个分离物都有两个质粒，一个主要质粒大小约为 60kb，另一个较小质粒大小约为 3.2kb。两种分离物的 atzA-F 基因均位于较大的质粒内，而 puhA 和 copA 基因则位于较小的质粒中。进行了酶切反应，结果表明，使用不同的限制酶对 ~ 60-Kb 质粒进行酶切，显示出相同的限制图谱，这表明这两种分离物中都发现了携带完整莠去津降解途径的质粒。这些结果表明这些质粒的分散以及两种分离物对广泛应用于世界各地不同作物类型的莠去津和敌草隆的多除草剂降解潜力。
