| Understanding the abundance of important antibiotic resistance genes (ARGs) in drinking water sources and agricultural regions is of high interest due to its potential public health risk in accelerated dissemination of a wide spectrum of antibiotic resistance. However, little is known about the distribution of ARGs in Yangcheng Lake, Kunshan, China. In this study, in order to generate a relatively comprehensive ARGs profile, a weekly time-series sampling was conducted from June 2021 to August 2022 in two sites of Eastern Yangcheng Lake. The absolute ARGs abundance was quantified by real-time quantitative polymerase chain reaction (qPCR). Twelve genes and one mobile genetic element (integron 1) were measured, and this study will mainly focus on mphA, sul(II), sul(III), blaOXY, ermB, aac6ib and int1, among which the abundance of sul(II) > blaOXY > aac6ib > mphA > ermB > sul(III) was determined across all seasons. A seasonal trend was observed that warmer seasons from April to September were beneficial for resistance gene proliferation and transmission. Moreover, potential driving mechanisms for the prevalence of antibiotic resistance genes in various seasons were investigated. Nutrients, chlorophyll a, water temperature and mobile genetic element (MGE) could respectively exert significant influence on the ARGs during different seasons. Additionally, multiple genes were found to be co-existing on certain ARG carriages, suggesting risks for multi-resistance transmission. This study was alarming about Yangcheng Lake as a reservoir of antibiotic resistance and multiple driving mechanisms of resistance, which potentially exhibited public health risks for human populations in proximity. |
