Choline phosphorylcholine

Barak, A. J. and Toma, D. J. (1981) Determination of choline, phosphorylcholine and betaine methods in enzymology, Lipids 72 (part D), 287-292. 

Houston, KM. and Harnett, W. (1999b) Mechanisms underlying the transfer of phosphorylcholine to filarial nematode glycoproteins - a possible role for choline kinase. Parasitology 118, 311-318. 

A more successful strategy for developing sensitive and facile assays to monitor PLCBc activity involves converting the phosphorylated headgroup into a colorimetric agent via a series of enzyme coupled reactions. For example, phosphatidylcholine hydrolysis can be easily monitored in a rapid and sensitive manner by enzymatically converting the phosphorylcholine product into a red dye through the sequential action of alkaline phosphatase, choline oxidase, and peroxidase [33]. This assay, in which 10 nmol of phosphorylcholine can be readily detected, may be executed in a 96-well format and has been utilized in deuterium isotope and solvent viscosity studies [34] and to evaluate inhibitors of PLCBc [33] and site-directed mutants of PLCBc [35,36]. 

In the human body choline is needed for the synthesis of phospholipids in cell membranes, methyl metabolism, transmembrane signaling and lipid cholesterol transport and metabolism [169]. It is transported into mammalian cells by a high-affinity sodium-dependent transport system. Intracellular choline is metabolized to phosphorylcholine, the reaction being catalyzed by the enzyme choline... 

Leon and Young found that the specificity of anti-pneumococcal C myeloma immunoglobulins is for the phosphorylcholine or choline determinant of this antigen.72 Many other antigens, such as polysaccharides from groups O and H streptococcus,66 Ascaris,73 Lac-... 

Dimyristoyl- and dipalmitoyllecithin were synthesized by acylation of sn-glycero-3-phosphorylcholine with fatty acid anhydrides as described by Cubero Robles and van den Berg (23). The sn-glycero-3-phosphoryl-choline was prepared by deacylation of egg-yolk lecithin according to... 

Phosphatidylserine, L-a-glyceryl-phosphorylcholine, and cytidine diphosphate choline have shown positive effects. 

The enzymatic radioassay method for the analysis of acetylcholine and choline in brain tissue has been reported by Reid et al. [210]. The method describes the determination of nanogram amounts of acetylcholine and choline in as little as 10 mg of brain tissue, involves isolation of acetylcholine by high-voltage paper electrophoresis, alkaline hydrolysis of acetylcholine to choline, and conversion of this into [32P]-phosphoryl choline in the presence of choline kinase and [y32P] ATP. The labeled derivative is isolated by column chromatography on Bio-Rad AG1-X8 resin, using Tris buffer solution as the eluent. Cerenkov radiation from 32P is counted (at 33% efficiency) in a liquid scintillation spectrometer. The amount of phosphorylcholine is proportional to the amount of choline over the range of 0.08-8.25 nmol. 

Figure 33.11. Binding of a Small Antigen. The structure of a complex between an Fj j, fragment of an antibody and its target in this case, phosphoryl-choline. Residues from the antibody interact with phosphorylcholine through...

Figure 17-5 Hypothetical model of synthesis, storage, and release of ACh. (I) ACh is released from storage granules under the influence of the nerve action potential and Ca (2) ACh acts on postsynaptic cholinergic receptors. (3) Hydrolysis of ACh by AChE occurs in the synaptic cleft. (4) A high-affinity uptake system returns choline to the c osol. (5) ChAT synthesizes ACh in the cytosol, and the ACh is stored in granules (6) Glucose is converted to pyruvate, which is converted to acetyl-CoA in the mitochondria. Acetyl-CoA is released from the mitochondria by an acetyl carrier (7) Choline is also taken up into the neuron by a low-affinity uptake system and converted partly to phosphorylcholine.

Tanaka, K., N.E. Tolbert, and A.F. Gohlke Choline kinase and phosphorylcholine phosphatase in plants Plant Physiol. 41 (1966) 307-312. 

Choline chloride dihydrogen phosphate Phosphorylcholine C5H,5CIN04P 107-73-3 219.606 vise lig ... 

Me- C] choline incorporated into phosphatidylcholine of cell membranes by phosphoryl choline transferase motion of the polar headgroup is similar to that for sonicated lipid vesicles large intracellular pool of phosphoryl [Me- C] choline exists. Ti values of intracellular phosphorylcholine Indicate that intracellular viscosity -1.2 times that of water. 

A substance with similar pharmacological activity could be obtained from a choline plasmalogen prepared from heart. The choline plasmalogen is now known to be glycerol l-alkenyl-2-acyl-3-phosphorylcholine (II) [see Gottfried and Rapport (1962), for references]. 

Because of its noninvasive nature, MRS is especially suited to in vivo studies of brain. Numerous cerebral metabolites are detectable, particularly with MRS (Figure 6). A few metabolites contribute prominent peaks and these are most easily quantifiable. Naa is predominantly found in the central nervous system, especially in neurons, although its functional role is not fully understood. Dynamic changes in brain Naa concentration have been observed reduced concentration may indicate neuronal dysfunction as well as loss. A prominent peak due to choline (Cho) has contributions from several metabolites including phosphorylcholine and glycerophosphorylcholine. Phosphatidylcholine is synthesized from chohne and is a major constituent of cell membranes being bound, this component is NMR invisible due to a very short T2. Pathologically increased membrane... 

Tanaka et al. (1966) detected choline kinase activity in leaves of barley (A. saliva L.), wheat (Triticum vulgare), tobacco (Nicotiana tabaccum L.), spinach Spinacea oleracea L.), and squash Cucurbita pepo L.). The characteristics of the enzyme were very similar to those described for rapeseed. A nonspecific phosphatase which hydrolyzed phosphorylcholine was also described. These authors pointed out that these two enzyme activities were far from sufficient to account for the rapid equilibration of POi with the large reserves of phosphorylcholine found in plants. There is still no satisfactory answer to this problem. 

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