Glycerophosphates

Lecithins are fatty acid esters of glycero-phosphoric acid derivatives. Commercially glycerophosphoric acid is used to prepare the medicinal glycerophosphate salts, c.g. the calcium salt. 

Disodium-0-glycerophosphate [819-83-0 (4H2O)] M 216.0, m 102-104°, pK O.OO (free acid). Crystd from water. 

Other pharmaceutical chemicals such as calcium gluconate, ferrous salts, nikethamide, glycerophosphates, chloral hydrate, saccharin, antihistamines (including meclozine, and buclozine), tranquilizers (including meprobamate and chloropromazine), antifilarials, diethylcarbamazine citrate, and oral antidiabetics, including tolbutamide and chloropropamide ... 

The Glycerophosphate Shuttle Ensures Efficient Use of Cytosolic NADH... 

In the glycerophosphate shuttle, two different glycerophosphate dehydrogenases, one in the cytoplasm and one on the outer face of the mitochondrial inner membrane, work together to carry electrons into the mitochondrial matrix (Figure 21.32). NADH produced in the cytosol transfers its electrons to dihydroxyaeetone phosphate, thus reducing it to glyeerol-3-phosphate. This metabolite is reoxidized by the FAD -dependent mitochondrial membrane enzyme to... 

FIGURE 21.33 The glycerophosphate shuttle (also known as the glycerol phosphate shuttle) couples the cytosolic oxidation of NADH with mitochondrial reduction of [FAD]. 

Figure 12-12. Glycerophosphate shuttle for transfer of reducing equivalents from the cytosol into the...

Alkaline phosphatase catalyzes the dephosphorylation of a mmber of artificial substrates ( ) including 3-glycerophosphate, phenylphosphate, p-nitrophenylphosphate, thymolphthalein phosphate, and phenolphthalein phosphate. In addition, as shown recently for bacterial and human enzymes, alkaline phosphatase simultaneously catalyzes the transphosphorylation of a suitable substance which accepts the phosphoryl radical, thereby preventing the accumulation of phosphate in the reaction mediim (25). 

Alkaline phosphatase assays based on 3-glycerophosphate now appears to be obsolete, and methods buffered by either glycine or barbital are also obsolete as these buffers inhibit ALP or are poor buffers. Serum alkaline phosphatase is known to be composed of several isoenzymes which presumably arise from bone, liver, intestine, and placenta. The placental alkaline phosphatase is known to be much more resistant to heat denaturation than the other isoenzymes, and this resistance provides a simple test for it (5). The other enzymes can be separated through the differential inhibition by phenylalanine, by electrophoresis and by specific antibodies. However, the clinical usefulness of the results obtained is in doubt (23). 

Acid phosphatase catalyzes the dephosphorylation of an artificial organic substrate, such as B-glycerophosphate, phenyl-phosphate or thymolphthalein monophosphate. The analyst may measure either the phosphate or the organic radical liberated. 

The first step of triglyceride biosynthesis is the formation of phosphatidic acid with the involvement of glycerophosphate acyltrans-ferase ... 

Useful serine/threonine protein phosphatase inhibitors include microcystin-LR (which inhibits protein phosphatases 1, 2A, and 2C, and related enzymes) and /1-glycerophosphate. Sodium fluoride may also be employed. Sodium orthovanadate inhibits protein tyrosine phosphatases. 

Richardson SM et al (2008) Human mesenchymal stem cell differentiation to NP-like cells in chitosan-glycerophosphate hydrogels. Biomaterials 29(1 ) 85—93... 

Inhibits alpha-glycerophosphate dehydrogenase activity in trout... 

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