Phosphate bis

H,COPO Ribulose-1,5-bis-phosphate (RuBP) carboxylase HCOH 1, H,C0P05 Two 3-Phospho- kinase 1,3-Blsphospho-glvcerate (BPG) dehydrogenase Glyceraldehydi 3-phosphate (G3P)... 

Transfer of the phosphoryl group to ADP in step 10 then generates ATP and gives enolpyruvate, which undergoes tautomerization to pyruvate. The reaction is catalyzed by pyruvate kinase and requires that a molecule of fructose 1,6-bis-phosphate also be present, as well as 2 equivalents of Mg2+. One Mg2+ ion coordinates to ADP, and the other increases the acidity of a water molecule necessary for protonation of the enolate ion. 

Figure 1. Simplified schematic of receptor-mediated signal transduction in neutrophils. Binding of ligand to the receptor activates a guanine-nucleotide-binding protein (G protein), which then stimulates phospholipase C. Phosphatidylinositol 4,5-bis-phosphate is cleaved to produce diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). DAG stimulates protein kinase C. IP3 causes the release of Ca from intracellular stores, which results in an increase in the cytosolic Ca concentration. This increase in Ca may stimulate protein kinase C, calmodulin-dependent protein kinases, and phospholipase A2. Protein phosphorylation events are thought to be important in stimulating degranulation and oxidant production. In addition, ionic fluxes occur across the plasma membrane. It is possible that phospholipase A2 and ionic channels may be governed by G protein interactions. ...

A structurally characterized example of a dinuclear zinc complex with a bridging phosphate monoester was provided by Kitajima and co-workers using the tris(pyrazolyl)borate ligand system. The P—O bond in a tris- or bis-phosphate ester is cleaved by a hydroxo zinc complex resulting in the monoester compound.443... 

The other activity associated with transmembrane receptors is phospholipase C. Phosphatidyl inositol is a membrane phospholipid that after phosphorylation on the head group is found in the membrane as a phos-photidylinostitol bis phosphate. Phospholipase C cleaves this into a membrane associated diacylglycerol (the lipid part) and inositol trisphosphate (IP3, the soluble part). Both play a later role in elevating the level of the second messenger, Ca2+. 

Secondary signals Glucose signals activate (fructose 2,6-bis-phosphate activates phosphofructokinase). Low-glucose signals inhibit. 

Developer Naphthol AS-BI phosphate (Sigma N4875) 2 mg, N,N-dimeth-ylformamid 0.2 mL, veronal-acetate buffer 9.8 mL, pH 9.2, levamisol 1 M... 

Develop with (naphthol AS-BI phosphate/Fast Red, fresh made) for 20 min in the dark (in tinfoil-sealed humidity chambers). For preparation of developer, see Subheading 5.1.1.1, item 4. 

Manganese(II)-A/, A/r -dipyridoxylethylenediamine-A/r, AT-diacetate 5,5 -bis(phosphate) 75 (DPDP) is clinically used for enhancing contrast in the liver (detection of hepatocellular carcinomas) (312). Some dissociation of Mn(II) appears to occur in the liver, and enhancement can also be obtained in functional adrenal tissues (313). Manganese(II)-tetrasulfonated phthalocyanine also shows tumor localization properties and is a more efficient relaxation agent than the analogous Gd(III) complexes (314). 

The interconversion of fructose-6-phosphate and fructose-1,6 bis phosphate is a control point in glycolysis and gluconeogenesis. Gluconeogenesis is a pathway which allows carbon atoms from substrates such as lactate, glycerol and some amino acids to be used for the synthesis of glucose, so it is in effect physiologically the opposite of... 

PFK = phosphofructokinase PK = pyruvate kinase G-6-P = glucose-6-phosphate F-6-P = fructose-6-phosphate F-1,6bisP = fructose-1,6 bis phosphate... 

Figure 3.4 also shows that fructose-2,6-bis phosphate (F2,6bisP) is an important allosteric regulator of PFK-1 this is partly because the turnover of F2,6bisP influenced by the hormone glucagon. F2,6bisP is synthesized from fructose-6-phosphate by PFK-2,... 

RAMA rabbit muscle aldolase (fructose-1,6-bis-phosphate aldolase)... 

The same basic biochemical control mechanism causes contraction of the smooth muscle as well as secretion of aldosterone. The binding of angiotensin to its receptor activates a membrane phospholipase-C. It catalyses the hydrolysis of phosphoinositide phosphatidylinositol bis-phosphate to produce the two intracellular messengers, inositol trisphosphate (IP3) and diacylglycerol (DAG). 

This enzyme [EC S.4.2.8] catalyzes the interconversion of D-mannose 1-phosphate and D-mannose 6-phosphate. Either D-mannose 1,6-bisphosphate or D-glucose 1,6-bis-phosphate can act as the cofactor. 

Figure 1.11 Pathways involved in phospholipase C (PLC) cellular signalling. PKA, protein kinase A or cAMP-dependent protein kinases PKC, protein kinase C PI, phosphatidylinositol PIP2, phosphatidylinositol bis-phosphate IP3, inositol triphosphate IP, inositol phosphate DAG, diacylglycerol.

Develop the alkaline phosphatase with fast red dissolve 5 mg sodium naphthol AS BI phosphate in dimethylformamide (few drops) and add to 5 mg fast red TR salt in 10 ml veronal acetate buffer (pH = 9.2), incubate the slides for 1 h Wash with tap water Counterstain as desired... 

Many enzymes are regulated by covalent modification, most frequently by the addition or removal of phosphate groups from specific serine, threonine, or tyrosine residues of the enzyme. In the fed state, most of the enzymes regulated by covalent modification are in Ihe dephosphorylated form and are active (see Figure 24.2). Three exceptions are glycogen phosphorylase (see p. 129), fructose bis-phosphate phosphatase-2 (see p. 98), and hormone-sensitive lipase of adipose tissue (see p. 187), which are inactive in their dephosphorylated state. 

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