Studies on the intestinal disaccharidases of the pigeon. II. Subcellular localization and solubilization
Prakash, K.; Patil, S.D.; Hegde, S.N.
Archives Internationales de Physiologie et de Biochimie 90(4): 255-264
1982
ISSN/ISBN: 0003-9799 PMID: 6188428 Document Number: 195926
In the pigeon, 70-80% of the activities of maltase (.alpha.-D-glucoside glucohydrolase EC 3.2.1.20), sucrase (.alpha.-glucohydrolase, EC 3.2.1.48), isomaltase (dextran 6-.alpha.-D-glucan hydrolase, EC 3.2.1.10) and glucoamylase (1,4-.alpha.-D-glucan glucohydrolase, EC 3.2.1.3) were localized in the brush border membrane of intestinal epithelial cells. Of the total glycosidase activities in the mucosal homogenate, nearly 60-70% were recovered in the microsomal (105,000 .times. g) fraction, .apprx. 30% in the mitochondrial (22,000 .times. g) fraction and < 5% from the cytosol (105,000 .times. g supernatant) fraction. The hydrolases were solubilized by digestion with papain but not with trypsin, and the phosphate ion had a protective effect in the solubilization. Among detergents, Triton X-100 but not sodium deoxycholate, truly solubilized these enzymes.