Biochemical and immunochemical determination of (Na+ + K+)-ATPase content in subcellular fractions prepared from the avian salt gland: evidence for enzyme heterogeneity.
Subcellular membrane fractions were prepared from the salt glands of osmotically-stressed ducklings. Two fractions were characterized biochemically with respect to (Na+ + K+)-ATPase, alkaline phosphodiesterase I, succinate dehydrogenase, esterase, and galactosyltransferase activities and immunochemically with respect to (Na+ + K+)-ATPase. The ratios of the estimates of the (Na+ + K+)-ATPase contents obtained biochemically and immunochemically from the two fractions differed by more than 2 X. The results are consistent with the presence of at least two molecular species of (Na+ + K+)-ATPase, unevenly distributed between the two fractions.
D000818:Animals; D004372:Ducks; D004950:Esterases / Q000378:metabolism; D005700:Galactosyltransferases / Q000378:metabolism; D007123:Immunoelectrophoresis, Two-Dimensional; D012491:Salt Gland / Q000201:enzymology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013347:Subcellular Fractions / Q000378:metabolism; D013385:Succinate Dehydrogenase / Q000378:metabolism
D013385:Succinate Dehydrogenase; D005700:Galactosyltransferases; D004950:Esterases; D000254:Sodium-Potassium-Exchanging ATPase