ATP polyphosphate

Complexes of PolyP and PHB, similar to those in bacteria, were found in the membranes of the endoplasmic reticulum and mitochondria of animal cells (Reusch, 1989, 1999a, 2000 Reusch and Sadoff, 1988), which suggests their participation in the processes of transmembrane transfer. The most intriguing report was that the Ca-ATPase purified from human erythrocytes contains PolyPs and PHBs and that the plasma membrane Ca2+-ATPase may function as a polyphosphate kinase this exhibits ATP-polyphosphate transferase and polyphosphate-ADP transferase activities. These findings suggest a novel supramolecular structure for the functional Ca2+-ATPase and a new mechanism of uphill Ca2+ extrusion coupled with ATP hydrolysis (Reusch et al, 1997). 

The supply of Man to sensitive species also leads to decreases in phospho compounds such as ATP, polyphosphate, Glc 6-P and phosphoenolpyruvate, significant high-energy intermediates in further metabolism. The decreases of these are more pronounced than those of... 

P406 and P4Ow are the anhydrides of phosphorous acid and phosphoric acid, respectively. Polyphosphates are extended structures used (as ATP) by living cells to store and transfer energy. 

Figure 12 Gradient separation of bases, nucleosides and nucleoside mono- and polyphosphates. Column 0.6 x 45 cm. Aminex A-14 (20 3 p) in the chloride form. Eluent 0.1 M 2-methyl-2-amino-l-propanol delivered in a gradient from pH 9.9-100 mM NaCl to pH 10.0-400 mM NaCl. Flow rate 100 ml/hr. Temperature 55°C. Detection UV at 254 nm. Abbreviations (Cyt) cytosine, (Cyd) cytidine, (Ado) adenosine, (Urd) uridine, (Thyd) thymidine, (Ura) uracil, (CMP) cytidine monophosphate, (Gua) guanine, (Guo) guanosine, (Xan) xanthine, (Hyp) hypoxanthine, (Ino) inosine, (Ade) adenosine, (UMP) uridine monophosphate, (CDP) cytidine diphosphate, (AMP) adenosine monophosphate, (GMP) guanosine monophosphate, (IMP) inosine monophosphate, (CTP) cytidine triphosphate, (ADP) adenosine diphosphate, (UDP) uridine monophosphate, (GDP) guanosine diphosphate, (UTP) uridine triphosphate, (ATP) adenosine triphosphate, (GTP), guanosine triphosphate. (Reproduced with permission of Elsevier Science from Floridi, A., Palmerini, C. A., and Fini, C., /. Chromatogr., 138, 203, 1977.)...

A nucleoside consists of a purine or pyrimidine base linked to a pentose, either D-ribose to form a ribonucleo-side or 2-deoxy-D-ribose to form a deoxyribonucleoside. Three major purine bases and their corresponding ribo-nucleosides are adenine/adenosine, guanine/guanosine and hypoxanthine/inosine. The three major pyrimidines and their corresponding ribonucleosides are cytosine/ cytodine, uracil/uradine and thymine/thymidine. A nucleotide such as ATP (Fig. 17-1) is a phosphate or polyphosphate ester of a nucleoside. 

AOPCP, a, P-methylene-adenosine diphosphate APnA, diadenosine polyphosphate (n=3-6) ARL 67156,6-N,N-diethyl-D- 3,y-dibromomethylene ATP CMTA, 2-(3-cyano-4-isobutoxyphenyl)-4-methyl-5-thiazolecarboxylic acid EHNA, erythro-9-(2-hydroxy-3-nonyl)adenine NBTI, nitrobenzylthioinosine. 

Diadenosine polyphosphates are found in the synaptic granules of some nerves, can activate some P2 receptors and are degraded in the extracellular space. In neural tissues the activity of ectodiadenosine polyphosphatases is lower than ecto-ATP-diphosphohydrolase. Hence, the diadenosine polyphosphates have a longer half-life in the extracellular space than does ATP. 

Smith CL, Peterson CL (2005) A conserved Swi2/Snf2 ATPase motif couples ATP hydrolysis to chromatin remodeling. Mol Cell Biol 25 5880-5892 Steger DJ, Haswell ES, Miller AL, Wente SR, O Shea EK (2003) Regulation of chromatin remodeling by inositol polyphosphates. Science 299 114-116... 

Because many cells maintain ATP, ADP, and AMP concentrations at or near the mass action ratio of the adenylate kinase reaction, the cellular content of this enzyme is often quite high. A consequence of such abundance is that, even after extensive purification, many proteins and enzymes contain traces of adenylate kinase activity. The presence of this kinase can confound the quantitative analysis of processes that either require ADP or are carried out in the presence of both ATP and AMP. Furthermore, the equilibrium of any reaction producing ADP may be altered if adenylate kinase activity is present. To minimize the effect of adenylate kinase, one can utilize the bisubstrate geometrical analogues Ap4A and ApsA to occupy simultaneously both substrate binding pockets of this kinase . Typical inhibitory concentrations are 0.4 and 0.2 mM, respectively. Of course, as is the case for the use of any inhibitor, one must always determine whether Ap4A or ApsA has a direct effect on a particular reaction under examination. For example. Powers et al studied the effect of a series of o ,co-di-(adenosine 5 )-polyphosphates (e.g., ApnA, where n =... 

SORBITOL DEHYDROGENASE POLYPHOSPHATE GLUCOKINASE POLYPHOSPHATE KINASE Polypodal attachment, BIOMINERALIZATION Polyribonucleotide synthase (ATP),... 

ATP Triphosphate Chain Conformation. Much of the work in the area of ATP triphosphate chain conformation has been performed by Cleland and co-workers (14--16). Their studies on metal(III)ATP interactions with kinases have led to the classification of kinases according to the stereochemistry of the polyphosphate chain as it binds to the active site. For the kinases they studied (hexokinase, glycerokinase, creatine kinase, phosphofructokinase, 3-phosphoglycerate kinase, acetate kinase, arginine kinase, adenylate kinase and pyruvate kinase) it was found that B, y-bidentate chromi M(III)-ATP (CrATP) and not a,6,y-tridentate CrATP is a... 

After a carboxylate, the next most significant biological ligand for Mg + is a phosphate. Phosphates, in addition to being present as inorganic phosphate (Pi), also happily polymerize to form not only diphosphates (for example, PPi and ADP) but also triphosphates (nucleoside triphosphates such as ATP). Many of these polyphosphates have fundamental biochemical importance as evidenced by the ATP ADP - - Pi reaction. 

Problem 22.47 Write the structural formulas for adenine monophosphate (amp) and triphosphate (atp) nucleotides, (atp is the most important source of energy for biochemical processes in living tissues the energy comes from the breaking of the high-energy polyphosphate bonds.)... 

S myo-inositol triphosphate -I- ATP <1> (<1> it appears that the enzyme utilizes inositol triphosphate as the initial substrate for the synthesis of higher myo-inositol polyphosphates [1]) (Reversibility <1> [1]) [1]... 

ATP -I- (phosphate)n = ADP -h (phosphate)rn-i (<12> mechanism [10] <12> short chain polyphosphates are incorporated at the ends of the long chain product [9] <12> both polyphosphate synthesis and polyphosphate utilization follow a processive mechanism [10])... 

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