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Kennedy Pathway
The CDP-choline pathway, first identified by Eugene P. Kennedy in 1956, is the predominant mechanism by which mammalian cells synthesize phosphatidylcholine (PC) for incorporation into membranes or lipid-derived signalling molecules. The CDP-choline pathway represents one half of what is known as the Kennedy pathway. The other half is the CDP-ethanolamine pathway which is responsible for the biosynthesis of the phospholipid phosphatidylethanolamine (PE). The CDP-choline pathway begins with the uptake of exogenous choline into the cell. The first enzymatic reaction is catalyzed by choline kinase (CK) and involves the phosphorylation of choline to form phosphocholine. Phosphocholine is then activated by the addition of Cytidine triphosphate, CTP catalyzed by the rate-limiting enzyme, Choline-phosphate cytidylyltransferase, CTP:phosphocholine cytidylyltransferase to form citicoline, CDP-choline. The final step of the pathway involves the addition of the choline headgroup onto a diacy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzymes Of The CDP-choline Pathway
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecules known as product (chemistry), products. Almost all metabolism, metabolic processes in the cell (biology), cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme, pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are Ribozyme, catalytic RNA molecules, called ribozymes. Enzymes' Chemical specificity, specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
