北京蔬菜地土壤中抗生素抗性基因与可移动元件的分布特征

Distribution Characteristics of Antibiotic Resistance Genes and Mobile Genetic Elements in Beijing Vegetable Base Soils

为揭示北京地区蔬菜土壤中抗生素抗性基因与可移动元件的分布特征应用高通量荧光定量PCR方法(HT-qPCR),选取北京3个区5个蔬菜基地进行调查研究.在蔬菜基地土壤中共检测到92~121种抗生素抗性基因,4~6种可移动元件,抗生素抗性基因及可移动元件按区分开.各蔬菜基地中共有且丰度较高的抗生素抗性基因型为:多重耐药类oprD、acrA-04和acrA-05,大环内酯类-林肯酰胺类-链阳性菌素B类抗生素抗性基因(MLSB)酰胺酶类fox5,万古霉素类vanC-03;共有可移动元件为intI1.蔬菜基地土壤中共检测到7种抗生素,含量较高的抗生素种类为恩诺沙星(ENR)、诺氟沙星(NOR)、土霉素(OTC)、磺胺甲噁唑(SMX).顺义区S1与S2蔬菜基地土壤中抗生素的种类与丰度均最高,依次是通州区T蔬菜基地、昌平区C2与C1蔬菜基地.相关性分析表明,蔬菜基地土壤中抗生素抗性基因丰度与抗生素丰度存在显著正相关(P <0.05).研究结果可为后续控制抗生素抗性基因的传播提供基础理论数据.

The distribution characteristics of antibiotic resistance genes( ARGs) and mobile genetic elements( MGEs) in five vegetable base soils from Beijing,China,were assessed. The composition of ARGs and MGEs in soil samples were analyzed by HTq PCR. We detected 92-121 ARGs and 4-6 MGEs. The ARGs and MGEs in vegetable base soils from different districts were separated from each other. The dominant ARGs shared by vegetable bases were opr D,acr A-04,and acr A-05 of a multidrug,mph A-01 of MLSB,and β-Lactamase fox5,van C-03 of vancomycin. The shared MGE among the five vegetable base soils was int I1. A total of seven antibiotics were detected in the soil of several vegetable bases. The dominant antibiotics included enoxacin( ENR),norfloxacin( NOR),oxytetracycline( OTC),and sulfamethoxazole( SMX). The numbers and abundance of antibiotics in the soil of vegetable bases from the Shunyi district were the highest,followed by those from Tongzhou and Changping. Correlation analysis showed that there was a significant positive correlation between the abundance of ARGs and the abundance of antibiotics in the soil of vegetable bases( P< 0. 05). These results provide basic theoretical data for controlling the transmission of ARGs.