Abstract
Parasite-derived proteases are important for the parasite life cycle and the pathogenesis of the disease they produce. Proteases of intestinal protozoan parasite Blastocystis hominis were studied for the first time with azocasein assays and gelatin SDS-PAGE analysis. Parasitic lysates were found to have high protease activity and nine protease bands of low (20–33 kDa) and high (44–75 kDa) molecular weights were reported. Proteases were found to be pH-dependent and highest proteolytic activity was observed at neutral pH. Inhibition studies showed that B. hominis isolate B, like many other protozoan parasites, contains mainly cysteine proteases.
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Acknowledgements
This research was supported by generous grants from the National Medical Research Council (R-182-000-058-213) and from the School of Medicine, National University of Singapore. We express appreciation to Ms. Geok Choo Ng and Mr. Ramachandran for technical support. Thanks are also due to Dr. Punam Dahiya, Ms. Tan Mui Hong, and Ms. Tan Li Li for their generous contributions. The present experiments were carried out in compliance with the laws and regulations of Singapore.
Selena W. S. Sio and Manoj K. Puthia contributed equally to this work.
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Sio, S.W.S., Puthia, M.K., Lee, A.S.Y. et al. Protease activity of Blastocystis hominis . Parasitol Res 99, 126–130 (2006). https://doi.org/10.1007/s00436-006-0131-1
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DOI: https://doi.org/10.1007/s00436-006-0131-1