Characterization of peptidases of adult Trichuris muris.
Excretory/secretory (E/S) material of Trichuris muris was found to contain 2 major peptidases, M(r) 85 and 105 kDa, which degrade gelatin optimally at pH 6.0 in sodium dodecyl sulphate-polyacrylamide gels. The peptidases were inactivated by diisopropylfluorophosphate, leupeptin and soybean trypsin inhibitor, but were unaffected by inhibitors of aspartic-, cysteine- and metallo-peptidases, indicating that they are serine peptidases. Both enzymes were detectable within 5 h after incubation of worms in culture medium and showed a time-dependent increase in levels. Neither peptidase was detected in worm extracts, suggesting that they are activated during or following secretion from worms. Live worms degraded a radio-isotope labelled extracellular matrix protein substratum derived from mammalian cells. Aminopeptidase activities capable of catalysing hydrolysis of amino acyl aminomethylcoumarin (MCA) substrates and a Z-Phe-Arg-MCA-hydrolysing cysteine peptidase activity, were detected in extracts of adult worms but not in E/S material.
Department of Biology, Imperial College of Science, Technology and Medicine, Prince Consort Road, South Kensington, London.
L J
LJ
Drake
A E
AE
Bianco
D A
DA
Bundy
F
F
Ashall
D000595:Amino Acid Sequence; D000626:Aminopeptidases / Q000302:isolation & purification / Q000378:metabolism; D000818:Animals; D003374:Coumarins / Q000737:chemistry; D003546:Cysteine Endopeptidases / Q000302:isolation & purification / Q000378:metabolism; D010450:Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009842:Oligopeptides / Q000737:chemistry; D011480:Protease Inhibitors / Q000494:pharmacology; D012697:Serine Endopeptidases / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity; D014258:Trichuris / Q000201:enzymology*
D003374:Coumarins; D009842:Oligopeptides; D011480:Protease Inhibitors; D010450:Endopeptidases; D000626:Aminopeptidases; D012697:Serine Endopeptidases; D003546:Cysteine Endopeptidases