title: Antimicrobial activity of synthetic all-D mastoparan M.
abstract: Mastoparan M, a tetradecapeptide toxin (INKAIAALAKKLL-NH2) from hornet venom and its D-form mastoparan M were synthesized chemically. All D- and L-mastoparan M forms were found to adopt 28% alpha-helical structures in a 30% trifluroethanol solution as shown by the circular dichroism spectrum. All-D mastoparan M caused 3H-thymidine release from labeled bacterial cells after incubation for 1 h and complete cell lysis by 4 h. Both L- and D-mastoparan M showed strong activity against gram-positive and gram-negative bacteria. All-D mastoparan M showed 2-fold higher antibacterial activity than L-mastoparan M. The effects of all-D mastoparan M on the surface morphology of Staphylococcus aureus (ATCC29213) and Escherichia coli (ATCC25922) were studied by scanning-beam electron microscopy. Blast-like bleb extrusions on the surface of some S. aureus and swellings on the end of E. coli were seen after culture with all-D mastoparan M. These findings indicated the all-D mastoparan M could kill bacteria by disrupting cells.
authors.affiliation: Department of Biology, National Taiwan Normal University, Taipei, ROC.
authors.forename: M L
authors.initials: ML
authors.lastname: Li
authors.forename: R W
authors.initials: RW
authors.lastname: Liao
authors.forename: J W
authors.initials: JW
authors.lastname: Qiu
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Wang
authors.forename: T M
authors.initials: TM
authors.lastname: Wu
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002942:Circular Dichroism; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects / Q000254:growth & development / Q000648:ultrastructure; D013237:Stereoisomerism; D014862:Wasp Venoms / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; D014862:Wasp Venoms; C403864:mastoparan M