Search results
Results from the WOW.Com Content Network
The cytosolic acetyl-CoA can also condense with acetoacetyl-CoA to form 3-hydroxy-3-methylglutaryl-CoA which is the rate-limiting step controlling the synthesis of cholesterol. [16] Cholesterol can be used as is, as a structural component of cellular membranes, or it can be used to synthesize steroid hormones , bile salts , and vitamin D .
Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle.All genomes sequenced to date encode enzymes that use coenzyme A as a substrate, and around 4% of cellular enzymes use it (or a thioester) as a substrate.
The synthesis of even-chained fatty acid synthesis is done by assembling acetyl-CoA precursors, however, propionyl-CoA instead of acetyl-CoA is used as the primer for the biosynthesis of long-chain fatty acids with an odd number of carbon atoms. [19] Regulation. In B. subtilis, this pathway is regulated by a two-component system: DesK and DesR.
In enzymology, an alcohol O-acetyltransferase (EC 2.3.1.84) is an enzyme that catalyzes the chemical reaction acetyl-CoA + an alcohol ⇌ {\displaystyle \rightleftharpoons } CoA + an acetyl ester Thus, the two substrates of this enzyme are acetyl-CoA and alcohol , whereas its two products are CoA and an acetyl ester .
ATP + Acetate + CoA → AMP + Pyrophosphate + Acetyl-CoA [1] Once acetyl-CoA is formed it can be used in the TCA cycle in aerobic respiration to produce energy and electron carriers. This is an alternate method to starting the cycle, as the more common way is producing acetyl-CoA from pyruvate through the pyruvate dehydrogenase complex.
The cytosolic acetyl-CoA can be carboxylated by acetyl-CoA carboxylase into malonyl CoA, the first committed step in the synthesis of fatty acids, or it can be combined with acetoacetyl-CoA to form 3-hydroxy-3-methylglutaryl-CoA which is the rate limiting step controlling the synthesis of cholesterol. [47]
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
It begins with acetyl-CoA and involves the stepwise condensation of two-carbon units, typically derived from malonyl-CoA, to form increasingly longer carbon chains. In fatty acid synthesis, these chains are fully reduced after each elongation step, while in polyketide synthesis, the reduction steps may be partially or completely omitted ...