Xuelian Zhang1, Yan Li1, Weiwei Wang1, Jing Zhang1, Yuan Lin2, Bin Hong1, Xuefu You1, Danqing Song1, Yanchang Wang3, Jiandong Jiang4, Shuyi Si5. 1. Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. 2. Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China; State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. 3. Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL, USA. Electronic address: yanchang.wang@med.fsu.edu. 4. Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China; State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. Electronic address: jiang.jd@163.com. 5. Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. Electronic address: sisyimb@hotmail.com.
Abstract
INTRODUCTION: The emergence of drug-resistant Gram-negative bacteria is a serious clinical problem that causes increased morbidity and mortality. However, the slow discovery of new antibiotics is unable to meet the need for treating bacterial infections caused by drug-resistant strains. Lipopolysaccharide (LPS) is synthesized in the cytoplasm and transported to the cell envelope by the LPS transport (Lpt) system. LptA and LptC form a complex that transports LPS from the inner membrane to the outer membrane. METHODS: This study performed a screen for agents that disrupt the transport of LPS in Gram-negative bacteria Escherichia coli. It established a yeast two-hybrid system to detect LptA-LptC interaction and used this system to identify a compound, IMB-881, that blocks this interaction and shows antibacterial activity. RESULTS: This study demonstrated that the IMB-881 compound specifically binds to LptA to disrupt LptA-LptC interaction using surface plasmon resonance assay. Overproduction of LptA protein but not that of LptC lowered the antibacterial activity of IMB-881. Strikingly, Escherichia coli cells accumulated 'extra' membrane material in the periplasm and exhibited filament morphology after treatment with IMB-881. CONCLUSION: This study successfully identified, by using a yeast two-hybrid system, an antibacterial agent that likely blocks LPS transport in Gram-negative bacteria.
INTRODUCTION: The emergence of drug-resistant Gram-negative bacteria is a serious clinical problem that causes increased morbidity and mortality. However, the slow discovery of new antibiotics is unable to meet the need for treating bacterial infections caused by drug-resistant strains. Lipopolysaccharide (LPS) is synthesized in the cytoplasm and transported to the cell envelope by the LPS transport (Lpt) system. LptA and LptC form a complex that transports LPS from the inner membrane to the outer membrane. METHODS: This study performed a screen for agents that disrupt the transport of LPS in Gram-negative bacteria Escherichia coli. It established a yeast two-hybrid system to detect LptA-LptC interaction and used this system to identify a compound, IMB-881, that blocks this interaction and shows antibacterial activity. RESULTS: This study demonstrated that the IMB-881 compound specifically binds to LptA to disrupt LptA-LptC interaction using surface plasmon resonance assay. Overproduction of LptA protein but not that of LptC lowered the antibacterial activity of IMB-881. Strikingly, Escherichia coli cells accumulated 'extra' membrane material in the periplasm and exhibited filament morphology after treatment with IMB-881. CONCLUSION: This study successfully identified, by using a yeast two-hybrid system, an antibacterial agent that likely blocks LPS transport in Gram-negative bacteria.
Authors: Alessandra M Martorana; Elisabete C C M Moura; Paola Sperandeo; Flavia Di Vincenzo; Xiaofei Liang; Eric Toone; Pei Zhou; Alessandra Polissi Journal: Front Mol Biosci Date: 2021-12-22