Cholesterol biosynthesis pathway
Cholesterol is an essential component of cell membranes and the precursor for the synthesis of steroid hormones and bile acids. The synthesis of this molecule occurs partially in a membranous world (especially the last steps), where the enzymes, substrates, and products involved tend to be extremely hydrophobic. The importance of cholesterol has increased in the past half-century because of its association with cardiovascular diseases, which are considered one of the leading causes of death worldwide. In light of the current need for new drugs capable of controlling the levels of cholesterol in the bloodstream, it is important to understand how cholesterol is synthesized in the organism and identify the main enzymes involved in this process. Taking this into account, this review presents a detailed description of several enzymes involved in the biosynthesis of cholesterol. In this regard, the structure and catalytic mechanism of the enzymes involved in cholesterol biosynthesis, from the initial two-carbon acetyl-CoA building block, will be reviewed and their current pharmacological importance discussed. We believe that this review may contribute to a deeper level of understanding of cholesterol metabolism and that it will serve as a useful resource for future studies of the cholesterol biosynthesis pathway.
The pathway of cholesterol synthesis is quite ..
Low HDL-cholesterol is a component of the metabolic syndrome that is characterized by obesity, insulin resistance, dyslipidemia, and hypertension
Metabolism1.0 Global and overview maps1.1 Carbohydrate metabolism1.2 Energy metabolism1.3 Lipid metabolism1.4 Nucleotide metabolism1.5 Amino acid metabolism1.6 Metabolism of other amino acids1.7 Glycan biosynthesis and metabolism1.8 Metabolism of cofactors and vitamins1.9 Metabolism of terpenoids and polyketides1.10 Biosynthesis of other secondary metabolites1.11 Xenobiotics biodegradation and metabolism1.12 Chemical structure transformation maps
Lipid metabolism - What Is Life?
About 40% of the bodies caloric intake is derived from lipids and almost all of these calories come from fats, the . The fatty acid composition in terms of saturation (oxidation forms) is not uniform but varies with the origin. Plant fats contain more polyunsaturated fatty acids and animal fats contain more saturated fatty acids as well as cholesterol. Polyunsaturated fats are essential for humans because animals are not able to synthesize those on their own. Most lipids, however, have metabolic functions contributing to membrane structures and signaling. (C20:4) is a fatty acid which plays a central role as precursor for prostaglandin synthesis. Phospholipids are synthesized from diacylgycerolphosphate, a negatively charged phospholipid precursor and signaling molecule itself, carrying various hydrophilic and/or charged headgroups that determine the surface charge and chemical properties of biological membrane surfaces.
Lipids and their role in metabolism
It causes shortening of the carbon chain from 30 to 27 carbons, removal of the two methyl groups at carbon 4, migration of the double bond from carbon 8 to carbon 5, and reduction of the double bond between carbon 24 and carbon 25.
~ Synthesis requires enzymes in both the cytosol and the membrane of the smooth endoplasmic reticulum (ER).
~ The pathway is responsive to changes in cholesterol concentration, and regulatory mechanisms exist to balance
the rate of cholesterol synthesis within the body against the rate of