The potent anti-Staphylococcus aureus activity of a sterile rabbit inflammatory fluid is due to a 14-kD phospholipase A2
| Autor: | Jerrold Weiss, Yvette Weinrauch, L M Madsen, Peter Elsbach, A. Foreman |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Blood Bactericidal Activity
Staphylococcus aureus medicine.drug_class Antibiotics Microbial Sensitivity Tests medicine.disease_cause Phospholipases A Bacterial cell structure Microbiology Phospholipase A2 Cell Wall Neutralization Tests Extracellular medicine Animals Ascitic Fluid Humans Bacteria biology Immune Sera Cell Membrane Phosphatidylglycerols General Medicine biology.organism_classification Molecular Weight Phospholipases A2 Snake venom biology.protein Calcium Methicillin Resistance lipids (amino acids peptides and proteins) Rabbits Research Article |
| Zdroj: | Journal of Clinical Investigation. 97:250-257 |
| ISSN: | 0021-9738 |
| DOI: | 10.1172/jci118399 |
| Popis: | The cell-free fluid (ascitic fluid, AF) of a sterile inflammatory peritoneal exudate elicited in rabbits is potently bactericidal for complement-resistant gram-negative as well as gram-positive bacterial species. This activity is absent in plasma. We now show that essentially all activity in AF against Staphylococcus aureus is attributable to a group II 14-kD phospholipase A2 (PLA2), previously purified from AF in this laboratory. Antistaphylococcal activity of purified PLA2 and of whole AF containing a corresponding amount of PLA2 was comparable and blocked by anti-AF-PLA2 serum. At concentrations present in AF (approximately 10 nM), AF PLA2 kills > 2 logs of 10(6) S. aureus/ml, including methicillin-resistant clinical isolates, and other species of gram-positive bacteria. Human group II PLA2 displays similar bactericidal activity toward S. aureus (LD90 approximately 1-5 nM), whereas 14-kD PLA2 from pig pancreas and snake venom are inactive even at micromolar doses. Bacterial killing by PLA2 requires Ca2+ and catalytic activity and is accompanied by bacterial phospholipolysis and disruption of the bacterial cell membrane and cell wall. These findings reveal that group II extracellular PLA2, the function of which at inflammatory sites has been unclear, is an extraordinarily potent endogenous antibiotic against S. aureus and other gram-positive bacteria. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|