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A study of the reaction catalysed by the liver branching enzyme.

ABSTRACT: The mechanism of action of liver branching enzyme has been studied by using as substrate two polysaccharides in which the non-reducing ends had been labelled by incubation with phosphorylase and a trace amount of [(14)C]glucose 1-phosphate. After these polysaccharides had been treated with branching enzyme, their structure was analysed by periodate oxidation, by degradation with phosphorylase and amylo-(1-->6)-glucosidase and by degradation with pullulanase. All the results indicate that the branching enzyme catalyses the transfer from (1-->4)- to (1-->6)-linkage of a chain of glucose units, the minimum length of which is six glucose units. A maltodextrin containing 16 glucose units was not acted on by the branching enzyme.

SUBMITTER: Verhue W

PROVIDER: S-EPMC1264978 | biostudies-other | 1966 Apr

REPOSITORIES: biostudies-other

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Mechanistic studies of an unprecedented enzyme-catalysed 1,2-phosphono-migration reaction.

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