Ionophorous properties of the 20,000-dalton fragment of (Ca/sup 2 +/ + Mg/sup 2 +/)-ATPase in phosphatidylcholine: cholesterol membranes

Journal Article · Sun Jan 01 04:00:00 EST 1978 · J. Membr. Biol.; (United States)

DOI:https://doi.org/10.1007/BF01933480· OSTI ID:5774909

Shamoo, A E

The purified 20,000-dalton fragment of sarcoplasmic reticulum (Ca/sup 2 +/ + Mg/sup 2 +/)-ATPase has been shown to have Ca/sup 2 +/-selective ionophoric activity. The Ca/sup 2 +/-ionophoric fragment has been purified by either SDS-column chromatography or SDS-preparative gel electrophoresis. The Ca/sup 2 +/-ionophoric fragment has been subjected to prolonged dialysis to insure the removal of bound SDS from the fragment. The selectivity sequence of this fragment in black lipid membranes (BLM) formed from either oxidized cholesterol or phosphatidylcholine/cholesterol is the same, P/sub Ba/ > P/sub Ca/ > P/sub Sr/ > P/sub Mg/ > P/sub Mn/. This selectivity sequence is the same as that for the intact (Ca/sup 2 +/ + Mg/sup 2 +/)-ATPase. Treatment of the fragment with cholate to absolutely insure the removal of bound SDS resulted in the fragment having a selectivity sequence as above except that P/sub Mn/ > P/sub Mg/. This and other data indicate that the 20,000-dalton fragment is the site containing the Ca/sup 2 +/-ionophoric activity of the (Ca/sup 2 +/ + Mg/sup 2 +/)-ATPase.

• Research Organization: Rochester Univ., New York, NY
• OSTI ID: 5774909
• Journal Information: J. Membr. Biol.; (United States), Journal Name: J. Membr. Biol.; (United States) Vol. 43; ISSN JMBBB
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
551000* -- Physiological Systems
59 BASIC BIOLOGICAL SCIENCES
ALKALINE EARTH METALS
ATP-ASE
BARIUM
BIOMIMETIC PROCESSES
CALCIUM
CHOLESTEROL
CHROMATOGRAPHY
DIALYSIS
ELECTROPHORESIS
ELEMENTS
ENZYMES
ESTERASES
ESTERS
HYDROLASES
HYDROXY COMPOUNDS
LIPIDS
MAGNESIUM
MANGANESE
MEMBRANE TRANSPORT
MEMBRANES
METALS
MUSCLES
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PERMEABILITY
PHOSPHATASES
PHOSPHOLIPIDS
SEPARATION PROCESSES
STEROIDS
STEROLS
STRONTIUM
TRANSITION ELEMENTS