Lipid Requirement of Membrane-Bound 3-Oxosteroid delta4-delta5-Isomerase. Studies on Beef Adrenocortical Microsomes
نویسندگان
چکیده
منابع مشابه
Studies on Membrane-bound Receptors for Antigen
THE EFFECT OF POLYADENYLIC: polyundylic acid complexes (poly A:U) on the amount of antibody on the surface of various populations of mouse lymphoid cells has been investigated by means of a sensitive measure of such activity-the binding by primed cell populations of beta-galactosidase (betaGZ) as an antigen. The sensitivity derives from the liberation of fluorescein from an artificial substrate...
متن کاملCytochrome P-450 Reductase from Adrenocortical Microsomes
The interaction between P-450czl and NADPH-cytochrome P-450 reductase, both purified from bovine adrenocortical microsomes, has been investigated in a reconstituted system with a nonionic detergent, Emulgen 913, by kinetic analysis and gel filtrations. Steady state kinetic data in progesterone 2 1-hydroxylation showed formation of an equimolar complex between the two enzyme proteins at low Emul...
متن کاملThe mechanism of the delta5-3-ketosteroid isomerase reaction: absorption and fluorescence spectra of enzyme-steroid complexes.
AS-3-Ketosteroid isomerase of Pseudomonas testosteroni is a homogeneous and crystalline enzyme that promotes the irreversible conversion of A5-3-ketosteroids to A4-3-ketosteroids (1, 2). This enzyme is one of the most active catalytic proteins known, since each mole (molecular weight 40,800) converts 16.7 x lo6 moles of A5-androstene-3, 17-dione (I) to A4-androstene-3, 17dione (II) per minute a...
متن کاملStimulation of protein-bound iodine formation by lipid extracts from hog thyroid microsomes.
The lipid materials extracted from hog thyroid microsomes were found to contain factors which stimulated both the NADPH oxidation by NADPH-cytochrome c reductase and PBI formation by a reconstituted system containing the reductase as a hydrogen peroxide generator and thyroid peroxidase. For both reactions, the stimulating activity in the extracts from the other subcellular fractions was less th...
متن کاملLipid Peroxide Formation in Microsomes
or ferricyanide were not able to replace ascorbate and induce lipid peroxide formation. 2. The rate of ascorbate-induced peroxidation is optimum at pH 6-0 whereas the rate of the NADPH system is optimum at pH7-0. Both systems require phosphate for maximum activity. 3. Lipid peroxide formation occurs at the maximum specific rate in very dilute microsome suspensions (0-15mg. of protein/ ml.). 4. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: European Journal of Biochemistry
سال: 1976
ISSN: 0014-2956,1432-1033
DOI: 10.1111/j.1432-1033.1976.tb11151.x