title: Non-oxidative antibacterial activity of bovine neutrophil granule proteins towards mastitis pathogens.
abstract: Acid extracts of bovine neutrophil granules displayed potent antibacterial activity towards a number of mastitis pathogens in vitro. Killing of pathogens by acid extractable granule protein was dependent on incubation time, protein concentration, bacterial cell load, pH and ionic strength. Gram-negative and Gram-positive organisms showed variable sensitivity to granule extract. Strains of Staphylococcus aureus were the most resistant of tested organisms to granule extract. Gram-negative organisms were neither consistently more nor less sensitive than Gram-positive organisms. Maximal killing of Gram-positive pathogens, after 30 minutes exposure to granule extract at 37 degrees C, occurred between pH 7.0 and 8.0. The Gram-negative organism Escherichia coli B117 was more sensitive to neutrophil granule extract at pH 5.0.
authors.forename: P A
authors.initials: PA
authors.lastname: Grieve
authors.forename: T
authors.initials: T
authors.lastname: Mattila
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides; D001419:Bacteria / Q000276:immunology*; D001798:Blood Proteins / Q000276:immunology*; D002417:Cattle; D006863:Hydrogen-Ion Concentration; D008414:Mastitis, Bovine / Q000382:microbiology*; D009504:Neutrophils / Q000276:immunology*
chemical_list: D023181:Antimicrobial Cationic Peptides; D001798:Blood Proteins; C030509:neutrophil basic proteins