SHE, a Starch Hydrolytic Enzyme active in maize endosperm (Zea mays), and
the cDNA sequence encoding SHE are disclosed. The specificity of native,
purified SHE is similar, in general terms, to previously known
alpha-amylases. However, the activity of SHE toward amylopectin results
in hydrolysis products that are distinctly different from those of other
alpha-amylases. SHE, and its homologous equivalents in other plants such
as rice, Arabidopsis, apple and potato, can be used in starch processing
for generating different, e.g., larger sized, alpha-limit dextrins for
industrial use, as compared to those generated by previously known
alpha-amylases or other starch hydrolytic enzymes. In addition,
modification of the expression of this enzyme in transgenic maize plants
or in other transgenic organisms (including bacteria, yeast, and other
plant species) can be useful for the generation of novel starch forms or
altered starch metabolism.
