Major research findings on animal-derived bacterial resistance in China June 26, 2019 Source: Science Network Recently, Professor Liu Yahong from the College of Veterinary Medicine of South China Agricultural University, in the process of continuous drug resistance monitoring, found in the animal and breeding environment, the degrading enzyme Tet (X4) which can lead to the inactivation of the last line of defense drug Tigecycline (Tigecycline) . The study found that once bacteria acquire a gene encoding a degrading enzyme, they can obtain the ability to degrade all tetracycline antibiotics, including the newly approved FDA's Eravacycline. The discovery of the tetracycline-degrading enzyme may lead to adjustments in the use of tetracycline antibiotics in countries around the world, and will also affect the research and development direction and market prospects of tetracycline antibiotics to some extent. The article was published online recently in the topic of microbiology, Nature Microbiology. Professor Sun Jian from the College of Veterinary Medicine of South China Agricultural University and Chen Chong, a third-year doctoral student, are the co-first authors of this research paper. Liu Yahong, College of Veterinary Medicine, South China Agricultural University Professor, Professor Liao Xiaoping and Professor Chen Liang, Professor of the Hackensack-Meridian Center for Exploration and Innovation Health, are co-authors of this paper. The research was also supported by the Third Affiliated Hospital of Sun Yat-sen University, Huizhou Central Hospital, Second Hospital Affiliated to Suzhou University, First Affiliated Hospital of Sun Yat-sen University, Shanghai Pulmonary Hospital of Tongji University, and Columbia University of the United States. Relevant research has won the “13th Five-Year†National Key R&D Program (Project No.: 2016YFD0501300), the Ministry of Education “Innovation Team Development Plan†(Project No.: IRT_17R39) and the Guangdong Provincial Department of Education “Innovative Strong School Project†(Project No.: 2016KCXTD010) ) and other funding. Tigecycline is a third-generation tetracycline drug developed by Pfizer Inc. (formerly Wyeth) based on minocycline. In recent years, with the outbreak of carbapenems and colistin resistance, tigecycline has gradually become the "last line of defense" for humans to face multi-drug resistant bacterial infections. In this study, a tigecycline-resistant Escherichia coli was isolated from pig manure in 2017 and subsequently confirmed to carry a potential mobile tetracycline degrading enzyme named Tet (X4). Clonal expression indicated that Tet (X4) is capable of mediating high levels of resistance to all tetracyclines including tigecycline and iravalcycline. Further studies revealed that the tet(X4) gene is located in the Pan-host-type IncQ1 type plasmid, which can efficiently carry the tet(X4) gene to various clinically resistant strains of laboratory-preserved strains or even carbapenemase. It has been partially popular in Guangdong, Guangxi, Fujian, Jiangxi and Jiangsu. It is especially important that the plasmid in the clinical bacteria can assist in the rapid transfer of the IncQ1 plasmid carrying tet (X4), which further increases the risk of transmission of the drug resistance gene and poses a great challenge to clinical treatment. The problem of bacterial resistance has become a worldwide problem and has received widespread attention worldwide. In response to the current situation and problems of bacterial resistance in China, Professor Liu Yahong has made great achievements and established the only veterinary microbial resistance risk assessment laboratory in China. He has won the Education Minister Jiang Scholar Innovation Team and the Ministry of Science and Technology Key Field Innovation Team. The Ministry of Agriculture's innovation team and the Guangdong Provincial Natural Science Foundation Innovation Team and other honorary titles have trained a group of young talents represented by Professor Sun Jian. In the past five years, the team has published more than 180 SCI papers in authoritative journals such as Lancet Infect Dis, Nature Microbiology, and Trends in Microbiology. The related results have produced a wide range of influences at home and abroad, and directly affect the use of veterinary drugs at home and abroad. The adjustment of policies has important theoretical and practical significance. DOI: https://doi.org/10.1038/s41564-019-0496-4 Vsstech Co.,Ltd. , https://www.vsstechcctvsystem.com