title: iTRAQ-coupled 2-D LC-MS/MS analysis of cytoplasmic protein profile in Escherichia coli incubated with apidaecin IB.
abstract: Apidaecins refer to a series of proline-rich, 18- to 20-residue antimicrobial peptides produced by insects. Accumulating evidence that proline-rich antimicrobial peptides are not-toxic to human and animal cells makes them potential candidates for the development of novel antibiotic drugs. However, the mechanism of action was not fully understood. In this study, antibacterial mechanism of apidaecins was investigated. iTRAQ-coupled 2-D LC-MS/MS technique was utilized to identify altered cytoplasmic proteins of Escherichia coli incubated with one isoform of apidaecins--apidaecin IB. The production of the chaperonin GroEL and its cofactor GroES, which together form the only essential chaperone system in E. coli cytoplasm under all growth conditions, was decreased in cells incubated with apidaecin IB. The decreasing of the GroEL-GroES chaperone team was further found to be involved in a new antibacterial mechanism of apidaecins. Our findings therefore provide important new insights into the antibacterial mechanism of apidaecins and perhaps, by extension, for other proline-rich antimicrobial peptides.
authors: School of Chemical and Biomedical Engineering, College of Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore.
authors: Yusi
authors: Y
authors: Zhou
authors: Wei Ning
authors: WN
authors: Chen
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D018835:Chaperonin 10 / Q000096:biosynthesis*; D018834:Chaperonin 60 / Q000096:biosynthesis*; D002853:Chromatography, Liquid; D003593:Cytoplasm / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000096:biosynthesis*; D020869:Gene Expression Profiling; D050956:HSP40 Heat-Shock Proteins / Q000096:biosynthesis; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis; D006360:Heat-Shock Proteins / Q000096:biosynthesis; D053719:Tandem Mass Spectrometry
chemical_list: D023181:Antimicrobial Cationic Peptides; D018835:Chaperonin 10; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; C489400:GrpE protein, E coli; D050956:HSP40 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C061361:apidaecin; C063842:dnaK protein, E coli