Cholesterol is a major constituent of the membranes in most eukaryotic cells where it fulfills multiple functions. Cholesterol regulates the physical state of the phospholipid bilayer, affects the activity of several membrane proteins, and is the precursor for steroid hormones and bile acids. Cholesterol plays a crucial role in the formation of membrane microdomains such as "lipid rafts" and ca...

Idescribe an assay for total cholesterol in serum, with use of the AutoAnalyzer ii (Technicon), in which cholesterol esters are saponified by alkali, cholesterol is held in aqueous micellar solution with a surfactant (Triton X-100) and oxidized by cholesterol oxidase, and the hydrogen peroxide produced is measured by chelation with Ti4+ and xylenol orange. An assay for free cholesterol in serum...

A soluble rat liver protein that stimulates microsomal methyl sterol oxidase activity has been isolated and purified to homogeneity by salt fractionation, differential heat inactivation, two calcium phosphate gel association, and Sephadex filtration. The protein, as isolated, may be dissociated with detergent into subunits with a molecular weight of approximately 10,300, as determined electroph...

A high sensitive and stable amperometric biosensor was developed using cholesterol oxidase, chitosan and multiwall carbon nano tubes (MWCNT’s) in order to determine total cholesterol in serum samples. Cholesterol oxidase was covalently immobilized on MWCNT’s; this enzyme was coated over glassy carbon electrode (GCE) and then a layer of chitosan deposited to prevent enzyme leaching. The ChOx/MWC...

Brevibacterium sterolicum possesses two forms of cholesterol oxidase, one containing noncovalently bound FAD, the second containing a FAD covalently linked to His(69) of the protein backbone. The functional role of the histidyl-FAD bond in the latter cholesterol oxidase was addressed by studying the properties of the H69A mutant in which the FAD is bound tightly, but not covalently, and by comp...

BACKGROUND Cholesterol oxidase is an alcohol dehydrogenase/oxidase flavoprotein that catalyzes the dehydrogenation of C(3)-OH of cholesterol. It has two major biotechnological applications, i.e. in the determination of serum (and food) cholesterol levels and as biocatalyst providing valuable intermediates for industrial steroid drug production. Cholesterol oxidases of type I are those containin...