ISSN:
1573-1561
Keywords:
α-Amylase inhibitors
;
trypsin inhibitors
;
cereal endosperm
;
wheat
;
barley
;
Spodoptera frugiperda
;
digestive enzymes
;
midgut proteases
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Abstract The α-amylase activity was determined throughout the larval development of Spodoptera frugiperda. Maximal activities with optimal pH in the range 8.5–9.5 were found in last instars. Protein preparations enriched in heterotetrameric inhibitors from wheat flour were active towards gut amylases from last instars, while those corresponding to homodimeric and monomeric inhibitors showed low inhibition levels. These results were further supported by testing purified members of each inhibitor type and by analyzing the effects of the inhibitors on the amylase isoenzyme pattern from native PAGE. High levels of trypsin-like activity were also found in gut extracts from last instars. Different genetic variants of the major barley trypsin inhibitor were active against this gut enzyme. None of the other larval digestive protease activities (chymotrypsin-like, elastase-like, leucine aminopeptidase-like, and carboxypeptidase A and B-like) were inhibited, indicating that the barley inhibitor is specific towards trypsin-like enzymes.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/B:JOEC.0000006447.85514.8d
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