ISSN:
1399-3054
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
Starch debranching enzyme was purified from mung bean (Vigna radiata) cotyledons to investigate its properties and developmental pattern during and following germination. A debranching enzyme was purified up to the step where only a doublet of polypeptides with molecular masses of 99 and 101 kDa, respectively, was detected by SDS-PAGE. The enzyme is thought to be a single chain monomer, as the molecular mass of the enzyme determined by gel filtration was 72 kDa. Monoclonal antibodies raised against the purified preparation recognized the doublet, indicating that the two polypeptides have immunological homology to each other. The enzyme preparation showed a high activity with pullulan as a substrate, low activity with soluble starch and amylopectin, and no activity with glycogen. These substrate specificities indicate that the debranching enzyme from mung bean cotyledons is of the pullulanase type. Immunoblotting profiles revealed that the enzyme is present in dry seeds and decreases gradually after imbibition, suggesting the possibility that the pullulanase plays a role in developing mung bean cotyledons.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1399-3054.1997.tb01032.x
Permalink
