Hypodermin B, a trypsin-related enzyme from the insect Hypoderma lineatum. Comparison with hypodermin A and Hypoderma collagenase, two serine proteinases from the same source.

A Lecroisey; N T Tong; B Keil

doi:10.1111/j.1432-1033.1983.tb07560.x

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Hypodermin B, a trypsin-related enzyme from the insect Hypoderma lineatum. Comparison with hypodermin A and Hypoderma collagenase, two serine proteinases from the same source.

A Lecroisey·N T Tong·B Keil

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Abstract

Hypodermin B, a serine proteinase with a molecular weight of 23000, was purified to homogeneity from the larvae Hypoderma lineatum. It is stoichiometrically inhibited by diisopropylfluorophosphate and fully inactivated by N-tosyllysine chloromethyl ketone and soya bean and bovine pancreatic trypsin inhibitors. N-Tosylphenylalanine chloromethyl ketone and ovomucoid are without effect on its activity. Hypodermin B hydrolyses both amide and ester substrates of trypsin but does not display any chymotryptic activity on synthetic substrates. Its specificity on the B chain of insulin is slightly broader than that of bovine trypsin. Its amino acid composition and N-terminal sequence suggest structural homology with serine proteinases of the trypsin family and with two other serine proteinases, hypodermin A and Hypoderma collagenase, previously isolated from the same larvae. Hypodermins A and B are very similar with respect to their inhibition and specificity, they differ however strongly from Hypoderma collagenase.

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Amino Acid Sequence Amino Acids Animals Diptera Endopeptidases Larva Microbial Collagenase Molecular Weight Serine Endopeptidases Substrate Specificity Sulfhydryl Compounds Comparative Study Journal Article

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A Lecroisey, N T Tong, B Keil. 1983-08-01. Hypodermin B, a trypsin-related enzyme from the insect Hypoderma lineatum. Comparison with hypodermin A and Hypoderma collagenase, two serine proteinases from the same source.. https://doi.org/10.1111/j.1432-1033.1983.tb07560.x

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