title: An acidic phospholipase A₂ with antibacterial activity from Porthidium nasutum snake venom.
abstract: Snake venoms are complex mixtures of proteins among which both basic and acidic phospholipases A(2) (PLA(2)s) can be found. Basic PLA(2)s are usually responsible for major toxic effects induced by snake venoms, while acidic PLA(2)s tend to have a lower toxicity. A novel PLA(2), here named PnPLA(2), was purified from the venom of Porthidium nasutum by means of RP-HPLC on a C18 column. PnPLA(2) is an acidic protein with a pI of 4.6, which migrates as a single band under both non-reducing and reducing conditions in SDS-PAGE. PnPLA(2) had a molecular mass of 15,802.6 Da, determined by ESI-MS. Three tryptic peptides of this protein were characterized by HPLC-nESI-MS/MS, and N-terminal sequencing by direct Edman degradation showing homology to other acidic PLA(2)s from viperid venoms. PnPLA(2) displayed indirect hemolytic activity in agarose erythrocyte-egg yolk gels and bactericidal activity against Staphylococcus aureus in a dose-dependent manner, with a MIC and MBC of 32 μg/mL. In addition, PnPLA(2) showed a potent inhibitory effect on platelet aggregation with doses up to 40 μg/mL. This acidic PLA(2), in contrast to basic enzymes isolated from other viperid snake venoms, was not cytotoxic to murine skeletal muscle myoblasts C(2)C(12). This is the first report on a bactericidal protein of Porthidium nasutum venom.
authors.affiliation: Programa Ofidismo/Escorpionismo, Universidad de Antioquia, Street 62 No. 52-59, A.A. 1226, Medellín, Colombia. johana2104@gmail.com
authors.forename: Leidy Johana
authors.initials: LJ
authors.lastname: Vargas
authors.forename: Mónica
authors.initials: M
authors.lastname: Londoño
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Quintana
authors.forename: Carolina
authors.initials: C
authors.lastname: Rua
authors.forename: Cesar
authors.initials: C
authors.lastname: Segura
authors.forename: Bruno
authors.initials: B
authors.lastname: Lomonte
authors.forename: Vitelbina
authors.initials: V
authors.lastname: Núñez
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000032:analysis / Q000302:isolation & purification* / Q000633:toxicity; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D003435:Crotalid Venoms / Q000737:chemistry* / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D013058:Mass Spectrometry; D051379:Mice; D008969:Molecular Sequence Data; D032446:Myoblasts / Q000187:drug effects; D054467:Phospholipases A2 / Q000235:genetics* / Q000302:isolation & purification* / Q000633:toxicity; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013211:Staphylococcus aureus / Q000187:drug effects; D017819:Viperidae
chemical_list: D000900:Anti-Bacterial Agents; D003435:Crotalid Venoms; D054467:Phospholipases A2