Diacyl glycerol phosphates

Sodium bis(2-ethyl-l-hexyl) sulfosuccinate (Aerosol OT, AOT) sodium do-decylbenzene sulfonate (SDBS) sodium di-2-ethyl hexyl phosphate (NaDEHP) dioleyl phosphoric acid (DOLPA) di(tridecyl) phosphoric acid (DTDPA) sodium dodecyl sulfate (SDS) 1,3-dilauroyl glycerol-2-disodium phosphate (2-modified 1,3-diacyl glycerol)... 

The first steps of glycerophospholipid synthesis are shared with the pathway to triacylglycerols (Fig. 21-17) two fatty acyl groups are esterified to C-l and C-2 of L-glycerol 3-phosphate to form phosphatidic acid. Commonly but not invariably, the fatty acid at C-l is saturated and that at C-2 is unsaturated. A second route to phosphatidic acid is the phosphorylation of a diacyl-glycerol by a specific kinase. 

Abbreviations used EMSA, electrophoretic mobility shift analysis IMPase 1, inositol monophosphatase 1 inositol synthase, A/vo-inositol 3-phosphate synthase NCBI, National Center for Biotechnology Information PCR, polymerase chain reaction Rb, retinoblastoma protein tss, transcriptional start site IP3, Inositol trisphosphate DAG, diacyl glycerol FISH, fluorescent in situ hybridization. 

Figure 1. Schematic representation of the brain inositol signaling system. The quantities of IMPase isoenzymes and IPPase are increased by chronic lithium treatment occurring at either the gene or protein levels. Inositol in this diagram indicates the myo-inositol isomer. Calbindin -calcium binding protein DAG- diacyl glycerol Gq-GTP binding protein IMPase 1 — inositol mono phosphatase 1 IPPase- inositol polyphosphate 1-phosphatase Ins(l)P, Ins(3)P, Ins(4)P-inos-itol monophosphates Ins(l,3)P2 - inositol 1,3-bisphosphate Ins( 1,4)/ 2 - inositol 1,4-bisphos-phate Ins(3,4)/)2- inositol 3,4-bisphosphate Ins (1,4,5)P3 - inositol 1,4,5-trisphosphate Ins( 1,3,4)/ 3 - inositol 1,3,4-trisphosphate Li+-lithium PA - phosphatidic acid PI- phosphatidyl inositol PIP- phosphatidyl inositol 4-phosphate PIP2- phosphatidyl inositol 4,5-bisphosphate PIP3- phosphatidyl inositol 3,4,5 trisphosphate PLC - phospholipase-C, VPA-valproate.

Phosphatidylcholine specific phospholipase C (PLC) can be used for the hydrolysis of PC (and PX) affording natural diacyl glycerol (DAG ) and chohne phosphate (CP) (or corresponding organic phosphate, OP). Transesterification has not been observed with this enzyme. The substrate specificity is less broad than desirable for the synthesis of OP that is otherwise... 

Step 2 Phospholipase C hydrolyzes phosphatidylinositol diphosphate and releases diacyl glycerol (DG) and inositol-3-phosphate (IP3). 

You would expect to see reduced rates of synthesis of triacylglycerols, which use diacyl-glycerols as acceptors of activated acyl groups. In addition, phosphatidyl choline synthesis is dependent on the availability of diacylglycerols as acceptors of choline phosphate from CDP-choline. 

HT2 2A,2B,2C Gq/11 type Formation of dIacyl glycerol and Inositol phosphates via phospholipase C protein kinase C activation. 

Glycerolipids are derivatives of glycerol and fatty acids. Most brain glycerolipids are derivatives of phos-phatidic acid (PtdOH), which is diacylated sn-glycerol-3-phosphate. The notation sn refers to stereochemical... 

Figure 12.11 Phosphoglyceride structure. The members of this group are derivatives of the parent compound, l,2-diacyl-src-glycerol-3-phosphate (phosphatidic acid) in which X is a hydrogen atom. This is replaced by either an amino alcohol or a polyhydroxy residue. In phosphoglycerides derived from animal tissues R1 is usually a saturated acyl chain of between 16 and 20 carbon atoms and R2 is usually unsaturated. Polyunsaturated acyl chains containing 16 or 18 carbon atoms predominate in leaf phosphoglycerides and those of bacterial origin are often more complex.

This enzyme catalyzes the reaction of an acyl-CoA derivative with l-acyl-vn-glycerol 3-phosphate to generate coenzyme A and l,2-diacyl-5 n-glycerol 3-phosphate. The animal enzyme is reported to be specific for the transfer of unsaturated fatty acyl groups. Interestingly, the acyl-[acyl-carrier-protein] can also act as an acyl donor. 

The phospholipid monolayers examined in this study were all saturated, symmetric, 1,2-diacyl-j -glycero-3-phosphate-based lipids. Four different lipid headgroups attached to the phosphate were examined choline, ethanolamine, glycerol and serine. Each lipid features a glycerol backbone, two saturated fatty acid chains and a phosphatidyl headgroup. 

The structure of glycerophospholipids is characterized by a l,2-diacyl-3-phospho-5n-glycerol, or phosphatidyl moiety, and a variable headgroup linked to the phosphate. Major phosphoglycerides found in nature are phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylserine, phosphatidylinositol (PI), and diphospha-... 

Fatty acids are not directly Incorporated Into phospholipids rather, they are first converted In eukaryotic cells Into CoA esters. The subsequent synthesis of many diacyl glycero phospholipids from fatty acyl CoAs, glycerol 3-phosphate, and polar head-group precursors Is carried out by enzymes associated with the cytosolic face of the ER membrane, usually the smooth ER, In animal cells (Figure 18-4). Mitochondria synthesize some of their own membrane lipids and Import others. In photosynthetic tissues, the chloroplast Is... 

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