Cholesterol proteins

Molecular Interactions. Various polysaccharides readily associate with other substances, including bile acids and cholesterol, proteins, small organic molecules, inorganic salts, and ions. Anionic polysaccharides form salts and chelate complexes with cations some neutral polysaccharides form complexes with inorganic salts and some interactions are stmcture specific. Starch amylose and the linear branches of amylopectin form inclusion complexes with several classes of polar molecules, including fatty acids, glycerides, alcohols, esters, ketones, and iodine/iodide. The absorbed molecule occupies the cavity of the amylose helix, which has the capacity to expand somewhat to accommodate larger molecules. The starch—Hpid complex is important in food systems. Whether similar inclusion complexes can form with any of the dietary fiber components is not known. 

Food and Nutrition Board. (2005). Dietary Referenee Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids, http //www.nap.edu. The National Academies Press, Washington, D.C. 

Qeveral recent investigations using various physicochemical methods have provided convincing evidence to support the contention that the basic structure of most biological membranes consists of a phospholipid bilayer (1,2,3, 4). Studies on phospholipid model membranes can therefore be expected to yield relevant information on the role played by phospholipids in determining the characteristic properties of biological membranes (5). One important aspect of this problem concerns the mechanisms of interaction between the phospholipids and other membrane constituents such as cholesterol, proteins, and different inorganic... 

Institute of Medicine 2002. Dietary reference intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein, and amino acids. Food and Nutrition Board. National Academy Press, Washington, D.C. 

As a rule, the combined immobilization of oxidase and peroxidase on the electrode allows the determination of metabolite (S) concentration, even if negligibly small. This type of biosensor is the main one used for detection of any particular compound in blood or other multicomponent system glucose, ethanol, cholesterol, proteins, amino acids, etc. For example, for patients with diabetes a rapid analysis of their blood for glucose concentration is a vitally important procedure. We will not attempt to discuss in full all the existing types of biosensor we will just note that enzymatic and cell biosensors are the most widespread types of these appliances. Enzymatic biosensors are more appropriate to the subject of the current monograph and, therefore, they will be discussed below. 

The bifunctional reagent sebacoyl dichloride has been used to convert alcohols to acid chlorides, which, at pH 8.5, react readily with proteins. This procedure was used by Bailey and Butler to prepare a cholesterol-protein conjugate. 

In man and in other mammalian species, the major mass of the prostate, usually consisting of the right and left lateral and the middle lobes, is composed of alveoli lined with columnar epithelium embedded in a thick fibromuscular stroma. These alveoli constantly secrete a fluid which is drained off by a system of branching ducts that empty into the floor and lateral surfaces of the posterior urethra. The normal secretion is dependent upon the degree of androgenic stimulation and amounts to about 0.5-2 ml per day. The prostatic secretion, which is characterized by very high acid phosphatase activity, is a milky fluid which contains citric acid, choline, cephalin, cholesterol, proteins, and electrolytes similar to those found in the plasma. 

The nitroxide (33) closely resembles cholesterol in its physical and biological properties, and has been used as a spin-labelled analogue of cholesterol to investigate cholesterol-protein interactions in human high-density lipoprotein.146 The fluorescent cholesterol analogue A-(7-nitrobenz-2-oxa-l,3-diazole)-22-amino-23, 24-dinorchol-5-en-3p-ol (34) has been used as a substrate for lecithin cholesterol... 

Cholesterol Protein-Bound Iodine Total Iodine... 

These apparently antagonistic properties can however co-exist as shown by the way in which cell membranes operate (Fig. 1). The membranes occur in the form of a closed surface composed of a liquid film bathing in another immiscible liquid. They are essentially composed of a phospholipid bilayer integrating cholesterol, proteins and polysaccharides. 

Figure 14.4 Relative amounts of cholesterol, protein, triglyceride, and phosphoglyceride in the four classes of lipoproteins.

Sources Dietary Reference Intakes for Calcium, Phosphorous, Magnesium, Vitamin D, and Fluoride (1997) Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin Folate, Vitamin B, Pantothenic Acid, Biotin, and Choline (1998) Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids (2000) Dietary Reference hitakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc (2001) Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2002/2005) and Dietary Reference Intakes for Calcium and Vitamin D (2011). These reports may be accessed via www.nap.edu... 

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