Purification and characterization of a pig intestinal alpha-limit dextrinase

Eur J Biochem. 1983 Jan 17;130(1):147-53. doi: 10.1111/j.1432-1033.1983.tb07129.x.

Abstract

Mucosa from the duodenal and jejunal regions of pig small intestine was repeatedly freeze-thaw treated to solubilize an enzyme preparation, enriched in maltase, glucoamylase and alpha-limit dextrinase activities; isomaltase and sucrase remained essentially insoluble during the treatment. Chromatographic procedures, including ion-exchange, gel filtration and hydroxylapatite chromatography of the solubilized preparation, brought to homogeneity an alpha-glucosidase active towards maltose, alpha-limit dextrins and starch in decreasing order, with only a very weak capacity to hydrolyse alpha-1,6-linkages. Michaelis constants and maximal velocities, as well as relative rates of hydrolysis of several substrates, including maltodextrins and alpha-limit dextrins, were determined and served to characterize what seems to be a rather specific alpha-1,4-glucosidase. The participation of this enzyme in the hydrolysis of alpha-limit dextrins and more generally in pathways for starch breakdown in the pig digestive tract is examined and discussed.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Centrifugation, Density Gradient
  • Chromatography
  • Electrophoresis, Polyacrylamide Gel
  • Glucosidases / isolation & purification*
  • Intestinal Mucosa / enzymology
  • Intestine, Small / enzymology
  • Kinetics
  • Molecular Weight
  • Substrate Specificity
  • Swine
  • alpha-Glucosidases / analysis
  • alpha-Glucosidases / isolation & purification*

Substances

  • Glucosidases
  • alpha-Glucosidases