近日，广东工业大学环境健康与污染控制研究院、环境科学与工程学院安太成教授团队题为《Sub-lethal photocatalysis promotes horizontal transfer of antibiotic-resistance genes by conjugation and transformability》的学术论文在国际期刊Water Research (2022, 221：118808)杂志上发表，论文第一作者为硕士生吉昊，通讯作者为李桂英教授。

论文DOI：https://doi.org/10.1016/j.watres.2022.118808

论文网址：https://www.sciencedirect.com/science/article/abs/pii/S0043135422007618?via%3Dihub

由于最近频繁发生的重大公共卫生事件，耐药细菌(ARB)和抗生素抗性基因(ARGs)在水中的传播与扩散逐渐成为全球性问题。据此，本研究在亚致死光催化的条件下探讨了ARGs的水平转移机制。结果表明：当仅对供体细菌使用亚致死光催化诱导时，ARGs的接合转移频率最多增加3-6倍；而当仅对受体细菌进行诱导时，接合转移频率则表现出了抑制趋势。然而，当供体或受体细菌均预先被诱导一定的时间后，接合转移的频率可最多增加10-22倍。此外，还发现水平转移频率及其转移机制与氧化应激系统、ATP系统及相关基因的表达有关。最后，本文还研究了ARB胞外质粒的可转化性及其对水平基因转移的贡献。结果表明：转化频率约占转化子总数的50%，表明转化可能是ARB在水中进行ARGs水平转移的另一种主要模式。以上结果表明：在亚致死光催化条件下，ARGs的水平转移频率的增加可能来自于接合转移和转化，进而可能提升ARGs在水体环境中传播的风险。

图文摘要

论文的英文摘要附如下：

ABSTRACT：

The spread of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in water is increasingly becoming a worldwide problem due to frequent recent major public health events. Herein, the horizontal ARG transfer mechanisms were studied under sub-lethal photocatalysis. The results show that ARGs had at most a 3- to 6-fold increase in the conjugative transfer frequency when only donor bacteria were induced with sub-lethal photocatalysis, while the frequency exhibited a trend toward inhibition when only the recipient bacteria were induced. However, when the donor or recipient bacteria were induced beforehand for a specific time, the frequency increased by a maximum of 10 to 22-fold. Moreover, the horizontal transfer frequency and its mechanism were related to the oxidative stress systems, ATP systems and the expression of related genes. Furthermore, the transformability of extracellular plasmids of the ARB and the contribution in horizontal transfer were also studied. Results show that the transformation frequency accounted for up to 50% of the total number of transconjugants, indicating that transformation might be a primary mode of horizontal ARG transfer by ARB in water. All of the above results demonstrate that sub-lethal photocatalysis will increase the frequency of horizontal gene transfer of ARGs through both conjugative transfer and the transformation pathway, which increases the risk of ARB in aquatic environments.