ISSN:
0739-4462
Keywords:
protease inhibitors
;
insect immunity
;
Chemistry
;
Food Science, Agricultural, Medicinal and Pharmaceutical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
Notes:
Endotoxin and laminarin activated prophenoloxidase in the plasma of Manduca sexta hemolymph. Diisopropylfluorophosphate inhibited this activation, suggesting the presence of a serine protease in the activation cascade. Exogenously added proteases such as pronase, chymotrypsin, subtilisin, and thermolysin also activated prophenoloxidase in Manduca plasma. However, these enzymes did not cause any detectable activation of partially purified prophenoloxidase. Thermolysin and subtilisin mediated activation of prophenoloxidase was inhibited by p-nitrophenyl-p′-guanidobenzoate. Similarly, benzamidine inhibited prophenoloxidase activation catalyzed by thermolysin. Activity measurements reveal the activation of a serine protease prior to prophenoloxidase activation. These results indicate the presence of a precursor form for the serine protease which is responsible for prophenoloxidase activation in Manduca sexta hemolymph.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/arch.940050102
