title: Characterization of ampicillin-stressed proteomics and development of a direct method for detecting drug-binding proteins in Edwardsiella tarda.
abstract: Antibiotic-resistant Edwardsiella tarda poses a severe challenge to aquaculture. An understanding for antibiotic-resistant mechanisms is crucial to control the disease. The present study characterizes E. tarda ampicillin-stressed proteome and shows the importance of energy metabolism including the TCA cycle and glycolysis/gluconeogenesis in the antibiotic resistance. Further combination with antibiotic measurement develops a new method for identification of antibiotic-binding proteins out of differential abundances of proteins and results in determination of ETAE_0175 and ETAE_3367 as ampicillin-binding proteins in E. tarda. Genes of the two proteins are cloned and recombinant proteins are purified for validation of antibiotic-binding capability. Results show that higher binding capability is detected in ETAE_3367 than ETAE_0175. Out of the two proteins, ETAE_3367 is first reported here to be an antibiotic-binding protein, while ETAE_0175 homology in other bacteria has been shown to bind with other antibiotics. Bioinformatics analysis shows that ETAE_3367 may closely interact with aceF and sucA belonging to the TCA cycle and glycolysis/gluconeogenesis, respectively. These results indicate that energy metabolism contributes to ampicillin resistance in E. tarda and a new method to identify antibiotic-binding proteins is developed. These findings highlight the way to an understanding of antibiotic-resistant mechanisms in content of antibiotic-binding proteins.
  
  
  CONCLUSIONS
  Our data characterizes Edwardsiella tarda ampicillin-stressed proteome and shows the importance of energy metabolism including the TCA cycle and glycolysis/gluconeogenesis in the antibiotic resistance. Furthermore, a new method based 2-DE proteomics is developed for identification of antibiotic-binding proteins, which results in determination of ETAE_0175 and ETAE_3367 as ampicillin-binding proteins in E. tarda. ETAE_3367 is closely interacted with proteins of the TCA cycle and glycolysis/gluconeogenesis, suggesting the drug-resistant mechanism.
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China.
authors.forename: Xian-jie
authors.initials: XJ
authors.lastname: Liu
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China.
authors.forename: Wei-cong
authors.initials: WC
authors.lastname: Zhu
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China.
authors.forename: Yu-bin
authors.initials: YB
authors.lastname: Su
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China.
authors.forename: Chang
authors.initials: C
authors.lastname: Guo
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China.
authors.forename: Zhao-hai
authors.initials: ZH
authors.lastname: Zeng
authors.affiliation: Shenzhen Bioeasy Biotechnologies Co., Ltd. No. 11 R&D Centre, Bao'an District, Shenzhen 518100, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: Center for Proteomics and Metabolomics, State Key Laboratory of Bio-Control, MOE Key Lab Aquatic Food Safety, School of Life Sciences, Sun Yat-sen University, University City, Guangzhou 510006, People's Republic of China. Electronic address: pxuanx@sysu.edu.cn.
authors.forename: Xuan-xian
authors.initials: XX
authors.lastname: Peng
mesh_terms: D000667:Ampicillin / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D020609:Edwardsiella tarda / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics; D013312:Stress, Physiological / Q000187:drug effects* / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D000667:Ampicillin
keywords: 2-DE based proteomics; Ampicillin; Antibiotic-binding proteins; ETAE_0175; ETAE_3367; Edwardsiella tarda