Cholesterol-esterifying enzymes of foam cells isolated from atherosclerotic rabbit intima

doi:10.1016/0021-9150(73)90075-0

Atherosclerosis

Volume 18, Issue 3, November–December 1973, Pages 451-457

https://doi.org/10.1016/0021-9150(73)90075-0 Get rights and content

Abstract

The cholesterol-esterifying activity of whole and fractionated homogenates of foam cells isolated from atherosclerotic rabbit aortic intima was investigated using [1-¹⁴C]oleate and [4-¹⁴C]cholesterol as substrates. Two cholesterol-esterifying enzymes were demonstrated in the foam cell homogenates. The first had a pH optimum of 5.0; it incorporated both [1⁻¹⁴C]oleic acid and [4-¹⁴C]cholesterol into cholesterol ester without requirement for CoASH and ATP. Enzyme activity was present in both the supernatant and the particulate fractions. The second enzyme had a pH optimum of 7.5; it incorporated both [1-¹⁴C]oleic acid and [4-¹⁴C]cholesterol ester in the presence of CoASH and ATP, but not in their absence; most of this enzyme activity was present in the particulate fraction.

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^☆: The financial assistance of the National Heart Foundation of Australia and the Felton Bequest is gratefully acknowledged.

^∗: Present address: Department of Biochemistry, University of Melbourne.

^∗∗: Present address: CSIRO Division of Food Research, Meat Research Laboratory, Cannon Hill, Queensland (Australia).

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Research paperCholesterol-esterifying enzymes of foam cells isolated from atherosclerotic rabbit intima☆

Abstract

J. Atheroscler. Res.

J. Lipid Res.

Biochim. Biophys. Acta

J. Atheroscler. Res.

Atherosclerosis

Atherosclerosis

Biochim. Biophys. Acta

J. Biol. Chem.

Analyt. Biochem.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

J. Biol. Chem.

Research paper
Cholesterol-esterifying enzymes of foam cells isolated from atherosclerotic rabbit intima☆