Serine protease and phenoloxidase activities in hemocytes of Biomphalaria glabrata snails with varying susceptibility to infection with the parasite Schistosoma mansoni

• Verfasst von: Riad, Mahmoud [VerfasserIn]
• Verfasst von: Doenhoff, M. [VerfasserIn]
• Verfasst von: Kirschfink, Michael [VerfasserIn]
• Verfasst von: Ruppel, Andreas [VerfasserIn]
• Titel: Serine protease and phenoloxidase activities in hemocytes of Biomphalaria glabrata snails with varying susceptibility to infection with the parasite Schistosoma mansoni
• Verf.angabe: M. Bahgat, M. Doenhoff, M. Kirschfink & A. Ruppel
• Jahr: 2002
• Umfang: 6 S.
• Fussnoten: Gesehen am 03.05.2021
• Titel Quelle: Enthalten in: Parasitology research
• Ort Quelle: Berlin : Springer, 1928
• Jahr Quelle: 2002
• Band/Heft Quelle: 88(2002), 6, Seite 489-494
• ISSN Quelle: 1432-1955
• DOI: doi:10.1007/s00436-002-0595-6
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1756907838

Abstract

The snail Biomphalaria glabrata possesses hemocytes, which are supposed to interact with the larval stages of the human parasite Schistosoma mansoni. We describe trypsin-like serine protease(s) and phenoloxidase activities in lysates from these hemocytes. Both enzymes have activity optima around pH 9.5. The serine protease was inhibited by EDTA, PMSF, antipain and aprotinin, and the phenoloxidase activity by diethydithiocarbamate. By comparison, the serine protease activity in secretions of S. mansoni cercariae also had an alkaline pH optimum around 10.5 and was sensitive to the same inhibitors. In addition, serine protease activities from snails and cercariae had the same molecular mass of 28 kDa. However, the Km value of the serine protease(s) and the Ki values of different inhibitors were generally lower for the snail enzyme than for the cercarial enzyme. The serine protease activity varied among individual snails but activity in hemocyte lysates and hemolymph correlated strongly. There was no detectable difference in the levels of activity between snails which are susceptible or resistant to schistosome infection.