title: Antibiotic and synergistic effect of Leu-Lys rich peptide against antibiotic resistant microorganisms isolated from patients with cholelithiasis.
abstract: Pseudomonas aeruginosa has eventually developed resistance against flomoxef sodium, isepamicin and cefpiramide. Therefore, in this study, the antibacterial activity and synergistic effects of the amphipathic-derived P5-18mer antimicrobial peptide were tested against pathogens associated with cholelithiasis that have developed resistance against commonly used antibiotics. The results were then compared with the activities of the amphipathic-derived peptide, P5-18mer, melittin and common antibiotics. Growth inhibition of planktonic bacteria was tested using the National Committee for Clinical Laboratory Standards (NCCLS). The bactericidal activity of the antimicrobial peptides was measured using time-kill curves. Synergistic effects were evaluated by testing the effects of P5-18mer alone and in combination with flomoxef sodium, isepamicin or cefpiramide at 0.5xMIC. P5-18mer peptide displayed strong activity against pathogens and flomoxef sodium, isepamicin and cefpiramide-resistant bacteria cell lines obtained from a patient with gallstones; however, it did not exert cytotoxicity against the human keratinocyte HaCat cell line. In addition, the results of time-kill curves indicated that P5-18mer peptide exerted bactericidal activity against four strains of P. aeruginosa. Finally, the use of P5-18mer and antibiotics exerted synergistic effects against cell lines that were resistant to commonly used antibiotics. These results indicate that this class of peptides has a rapid microbicidal effect on flomoxef sodium, isepamicin and cefpiramide-resistant strains of P. aeruginosa. Therefore, these peptides may be used as a lead drug for the treatment of acquired pathogens from patients with cholelithiasis who are affected with antibiotic-resistant bacteria.
authors.affiliation: Research Center for Proteineous Materials (RCPM), Chosun University, Kwangju, Republic of Korea.
authors.forename: Nari
authors.initials: N
authors.lastname: Jeong
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Seong-Cheol
authors.initials: SC
authors.lastname: Park
authors.forename: Jong-Kook
authors.initials: JK
authors.lastname: Lee
authors.forename: Ramamourthy
authors.initials: R
authors.lastname: Gopal
authors.forename: Suyeon
authors.initials: S
authors.lastname: Yoo
authors.forename: Byoung Kwan
authors.initials: BK
authors.lastname: Son
authors.forename: Joon Soo
authors.initials: JS
authors.lastname: Hahm
authors.forename: Yoonkyung
authors.initials: Y
authors.lastname: Park
authors.forename: Kyung-Soo
authors.initials: KS
authors.lastname: Hahm
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D002460:Cell Line; D002511:Cephalosporins / Q000494:pharmacology; D002769:Cholelithiasis / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D004357:Drug Synergism; D005839:Gentamicins / Q000494:pharmacology; D006801:Humans; D008555:Melitten / Q000494:pharmacology; D008969:Molecular Sequence Data; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D002511:Cephalosporins; D005839:Gentamicins; C552549:P5-18mer peptide; D008555:Melitten; C016927:isepamicin; C036666:cefpiramide; C045693:flomoxef