Format

Send to:

Choose Destination
See comment in PubMed Commons below
Insect Biochem Mol Biol. 2001 Mar 15;31(4-5):415-23.

Preliminary characterisation of digestive proteases of the green mirid, Creontiades dilutus (Hemiptera: Miridae).

Author information

  • 1Division of Entomology CSIRO, GPO Box 1700, 2601, Canberra, Australia. colebatch@mpimp-golm.mpg.de

Abstract

Protease activities in the secreted saliva, salivary glands and midgut of the green mirid, Creontiades dilutus, were investigated. The saliva and salivary glands had more protease activity than the midgut, but no differences in protease activity levels were detected between male and female mirids, adult mirids and third instar nymphs, or between fed and starved mirids. In the salivary glands, chymotrypsin-like serine proteases predominated, as characterised by inhibitor specificity, basic pH optima, and hydrolysis of N-benzoyl-L-tyrosine p-nitroanilide and N-succinyl-ala-ala-pro-leu p-nitroanilide. The pH optimum of midgut extracts was acidic (pH 4), implying that acidic proteases predominate. However, protease activity was inhibited substantially by both aprotinin and E-64, suggesting the presence of both serine and cysteine proteases in the midgut of the green mirid.

PMID:
11222951
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk