Abstract
SummaryThe metacestodes ofTaenia pisiformishave been shown to contain a protease inhibitor capable of inactivating the esterolysis ofN-α-benzoyl-L-arginine ethyl ester (BAEE) andN-benzoyl-L-tyrosine ethyl ester (BTEE) by trypsin and chymotrypsin, respectively, of bovine, dog and rabbit origin, but not affecting the hydrolytic activity of subtilisin, elastase, collagenase, pepsin, rennin and papain. This inhibitor has been demonstrated in whole worm extracts and in the incubation medium ofin vitro-maintained, intact living metacestodes. The protease inhibitor which was purified by trichloroacetic acid precipitation, Sephadex G–100 chromatography and affinity chromatography on CNBr-activated Sepharose 4B–bovine chymotrypsin conjugate was soluble in 5% trichloroacetic acid, withstood heat up to 80°C, tolerated the pH range 1·5 to 9·0, was unaffected by 8 M urea or 0·2m2-mercaptoethanol and had a molecular weight of about 7000 to 7200, as calculated from its gel chromatographic behaviour. Complex formation between the inhibitor and the enzymes required 3–4 min for completion. The enzyme–inhibitor complex was not dissociated by 4mKC1. Activity determinations on bovine TPCK–trypsin and bovine chymotrypsin with BAEE and BTEE assays revealed that the inhibitory actions toward both enzymes are functions of the same or closely adjacent sites of the inhibitor molecule. The supposed function of the inhibitor is discussed.
Publisher
Cambridge University Press (CUP)
Subject
Infectious Diseases,Animal Science and Zoology,Parasitology
Reference32 articles.
1. Enzymuntersuch-ungen an Fischen. II. Trypsin- und α-Amylase-Inhibitoren;Reichenbach-Klinke;Archiv für Fischereiwissenschaft,1970
2. Die Darstellung haltbarer Labflüssigkeiten;Soxhlet;Milch-Zeitung,1877
3. Pepsin from pepsinogen;Rajagopalan;Journal of Biological Chemistry,1966
4. A Chymotrypsin Inhibitor From the Parasitic Nematode, Oesophagostomum radiatum
Cited by
14 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献