Ingle SS, Trivedi N, Prasad R, Kuruvilla J, Rao KK, Chhatpar HS. Aminopeptidase-N from the Helicoverpa armigera (Hubner) brush border membrane vesicles as a receptor of Bacillus thuringiensis crylac delta-endotoxin.
Curr Microbiol 2001;
43:255-9. [PMID:
11683359 PMCID:
PMC7082820 DOI:
10.1007/s002840010297]
[Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Brush border membrane vesicles (BBMVs) were prepared from the 2nd instar larvae of Helicoverpa armigera. Binding of the activated Cry1Ac of Bacillus thuringiensis (Bt) toxin was shown by immunoblot. A 120-kDa protein was identified as a receptor for the Cry1Ac type delta-endotoxin. The aminopeptidase-N activity of BBMVs was measured as the hydrolysis of L-leucine p-nitroanilide. The specific activity was 35 units/mg protein. The BBMV preparation also showed low level of alkaline phosphatase activity. Zn++ chelating agents 2,2'-dipyridyl and 1,10-phenanthroline inhibited aminopeptidase activity at 10 mM concentration, indicating the presence of zinc-dependent aminopeptidase in the brush border of H. armigera. The aminopeptidase activity was increased with increasing concentration of delta-endotoxin. The purified 120-kDa binding protein was N-terminally sequenced. The first 10-amino-acid sequence showed 60-77% similarity with human cysteine-rich secretory protein-1 precursor, inhibin alpha chain precursor. Salmonella flagellar hook protein and yeast carboxypeptidase S.
Collapse