title: Effective antimicrobial activity of Cbf-14, derived from a cathelin-like domain, against penicillin-resistant bacteria.
abstract: Cbf-14, a cationic peptide derived from a cathelin-like domain, was designed by inserting the highly α-helical sequence RLLR into an antibacterial sequence and deleting the inactive amino acids in Cbf-K16. Clinical penicillin-resistant isolates as well as NDM-1-carrying Escherichia coli and a correspondingly infected mice model were employed to evaluate Cbf-14 antibacterial activity. The results showed that Cbf-14 possessed potent antimicrobial effects with an MIC of 8-64 μg/ml, and killed almost all bacteria within 240 min. Cbf-14-treated mice achieved an 80% survival rate and approximate 2.5 log unit reduction in CFU in tissues; additionally, this peptide significantly suppressed the production of pro-inflammatory cytokines by the disaggregation of lipopolysaccharide (LPS), suggesting its anti-inflammatory effects. Furthermore, Cbf-14, concentration higher than 2 × MIC value, increased membrane uptake to NPN and PI dye by 96.2% and 63.7%, respectively, neutralised the negative zeta potential of LPS and bacteria surface, and induced 100% leakage of liposome-entrapped calcein and cytoplasmic membrane disruption of E. coli, indicating obvious membrane permeation. Finally, it bound to DNA and respectively evoked 85.0% and 63.3% inhibition of gene replication and protein expression of NDM-1 at sub-MIC concentration in E. coli BL21 (DE3)-NDM-1. These data indicated that Cbf-14 possessed effective antimicrobial activity against penicillin-resistant bacteria in vitro/vivo through membrane disruption, DNA binding, down-regulating NDM-1 expression by plasmid replication inhibition, and anti-inflammatory activity by LPS disaggregation, suggesting a potential anti-infective clinical agent.
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Lingman
authors.initials: L
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Yanrong
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Mengxiao
authors.initials: M
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Yuwei
authors.initials: Y
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Kang
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Hanhan
authors.initials: H
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China. Electronic address: doujie@cpu.edu.cn.
authors.forename: Jie
authors.initials: J
authors.lastname: Dou
authors.affiliation: State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 210009, PR China. Electronic address: cl_zhou@cpu.edu.cn.
authors.forename: Changlin
authors.initials: C
authors.lastname: Zhou
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology / Q000627:therapeutic use*; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry* / Q000494:pharmacology / Q000627:therapeutic use*; D001419:Bacteria / Q000187:drug effects* / Q000201:enzymology; D001424:Bacterial Infections / Q000188:drug therapy / Q000473:pathology; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000473:pathology; D051379:Mice; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology; D011506:Proteins / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D000893:Anti-Inflammatory Agents; D023181:Antimicrobial Cationic Peptides; D010406:Penicillins; D011506:Proteins; C084515:cathelin; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1
keywords: Antimicrobial activity; Cbf-14; DNA binding; Membrane permeation; NDM-1-carrying bacteria; Penicillin-resistant bacteria