Adenylate kinase and

For luciferin, a firefly luciferase cosubstrate, another method of retention has been evaluated which consisted of incorporating the substrate in acrylic microspheres during their formation, these last being then confined in a polymeric matrix31. Using the suitable co-immobilized enzymes (adenylate kinase and creatine kinase), the three adenylic nucleotides (ATP, ADP and AMP) could be assayed continuously and reproducibly with a selfcontainment working time of 3 h. 

Adenosine triphosphate (ATP) is one of the most important cofactors involved in many of the synthetic reactions going on within the cell. Its recent large scale in vitro enzymatic synthesis from adenosine and acetylphosphate is of particular interest. Three enzymes immobilized in polyacrylamide gel were used adenosine kinase, adenylate kinase and acetate kinase (lip. ... 

The energy charge quotient has a value of unity (or, 1.00) when only ATP is present and a value of zero when only AMP is present. Thus, the adenine nucleotide system is said to be fully charged at EC = 1 and fully discharged at EC = 0. At intermediate values, the adenine nucleotides are interconverted by adenylate kinase, and their concentrations are constrained by the adenylate kinase mass action ratio ... 

Quite a few enzymes have been reported to have this reaction scheme for example, hexokinase, adenylate kinase, and phosphofructokinase. ... 

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... 

Hamada, M. Kuby, S.A. Studies on adenosine triphosphate transphosphorylases. XIII. Kinetic properties of the crystalline rabbit muscle ATP-AMP transphorphorylase (adenylate kinase) and a comparison with the crystalline calf muscle and liver adenylate kinases. Arch. Biochem. Biophys., 190, 772-792 (1978)... 

Kawai, M. Uchimiya, H. Biochemical properties of rice adenylate kinase and subcellular location in plant cells. Plant Mol. Biol., 27, 943-951 (1995)... 

Diederichs, K. Schulz, G.E. Three-dimensional structure of the complex between the mitochondrial matrix adenylate kinase and its substrate AMP. Biochemistry, 29, 8138-8144 (1990)... 

Okajima, T. Fukamizo, T. Goto, S. Fukui, T. Tanizawa, K. Exchange of nucleoside monophosphate-binding domains in adenylate kinase and UMP/CMP kinase. J. Biochem., 124, 359-367 (1998)... 

Didanosine is a synthetic purine nucleoside analog that inhibits the activity of reverse transcriptase in HIV-1, HIV-2, other retroviruses and zidovudine-resistant strains. A nucleobase carrier helps transport it into the cell where it needs to be phosphorylated by 5 -nucleoiidase and inosine 5 -monophosphate phosphotransferase to didanosine S -monophosphate. Adenylosuccinate synthetase and adenylosuccinate lyase then convert didanosine 5 -monophosphate to dideoxyadenosine S -monophosphate, followed by its conversion to diphosphate by adenylate kinase and phosphoribosyl pyrophosphate synthetase, which is then phosphorylated by creatine kinase and phosphoribosyl pyrophosphate synthetase to dideoxyadenosine S -triphosphate, the active reverse transcriptase inhibitor. Dideoxyadenosine triphosphate inhibits the activity of HIV reverse transcriptase by competing with the natural substrate, deoxyadenosine triphosphate, and its incorporation into viral DNA causes termination of viral DNA chain elongation. It is 10-100-fold less potent than zidovudine in its antiviral activity, but is more active than zidovudine in nondividing and quiescent cells. At clinically relevant doses, it is not toxic to hematopoietic precursor cells or lymphocytes, and the resistance to the drug results from site-directed mutagenesis at codons 65 and 74 of viral reverse transcriptase. 

Thermal tolerance of isolated muscle tissue and of proteins, such as adenylate kinase and actomyosin, of small and large varieties of Black Sea horse-mackerel has been studied by Altukhov (1962) and Glushankova (1967). Johnston et al. (1973) focused on determining the thermoresistance of ATPase... 

Microorganisms, which contain the enzymes APS-reductase, ADP-sulfurylase, adenylate kinase and/or ATP-sulfurylase have a certain advantage over those lacking these enzymes, because in addition to photophosphorylation they can also perform a substrate phosphorylation. 

Ulschmid JK, Rahlfs S, Schirmer RH, Becker K (2004) Adenylate kinase and GTP AMP phosphotransferase of the malarial parasite Plasmodium falciparum. Central players in cellular energy metabolism. Mol Biochem Parasitol 136(2 ) 211-220... 

Gly-Lys-Thr/ Ser) is found in many proteins capable of binding ATP or GTP including adenylate kinase66 671 and the ras p21 protein68-691 (Fig. 11.7). The sequence corresponds to a flexible loop structure between a helix and / sheet the sequence of adenylate kinase and ras protein are residues 15-23 (Gly-Gly-Pro-Gly-Ser-Gly-Lys-Gly-Thr) and 10-17 (Gly-Ala-Gly-Gly-Val-Gly-Lys Ser), respectively. 

Thus, in E. coli and P. aeruginosa the PolyP AMP phosphotransferase activity is a result of the joint action of adenylate kinase and polyphosphate kinases. The occurrence of PolyP AMP phosphotransferase in the above bacteria has, however, no genetic confirmation. No such activity was observed in eucaryotes, in line with the absence of polyphosphate kinase. 

The first chiral phosphates to be used for stereochemical analyses were chiral phosphorothioates, which were used to determine the stereochemical courses of ribonuclease, UDP-glucose pyrophosphorylase, adenylate kinase and several other kinases and synthetases. The chiral phosphorothioates either had sulfur in place of an oxygen at an otherwise prochiral center of a phosphodiester or phosphoanhydride or stereospecifically placed sulfur and 180 (or nO) in a terminal phosphoryl group. The syntheses and configurational analyses of the most important of these compounds are outlined in the following. 

Fig. 14. Orientations of enzymatic phosphorylations of chiral [lsO]phosphorothioates.. Shown are the orientations of phosphorylation of AMPS by adenylate kinase and ATP and the phosphorylation of ADP/3S by pyruvate kinase and phosphoenolpyruvatc (PEP) and by acetate kinase and acetvl P...

Figure 9.46. Structures of Adenylate Kinase and Guanylate Kinase. The nucleoside triphosphate-binding domain is a common feature in these and other homologous nucleotide kinases. The domain consists of a central P-pleated sheet surrounded on both sides by a helices (highlighted in purple) as well as a key loop (shown in green).

Fig. 5.8. Stereochemical course of ATP hydrolysis by Fj. The chiral [ 0, O, 0]-thiophosphate librated was converted into ATPjSS by successive treatments with glycolytic enzymes, adenylate kinase and glycolytic enzymes. The resulting ATP/8S were analyzed by P-NMR [164].

The following method has been described for the assay of cyclic AMP [144, 145]. Cyclic AMP is converted to 5 -AMP with the aid of phosphodiesterase and then to ATP with myokinase (EC 2.V.4.3 ATP AMP phosphotransferase adenylate kinase) and pyruvate kinase (EC 2.7.1.40 ATP pyruvate phosphotransferase). ATP is measured by determining the orthophosphate which accumulates during incubation of ATP with a cycling system containing myosin, pyruvate kinase, and phosphoenol pyruvate. Alternately, the ATP is determined by its luminescent reaction with firefly luciferin and luciferase [145-147]. With a sensitivity to about 1 pmol/tube of cyclic AMP, this assay is almost as sensitive as the phosphorylase method, but with a linearity over three orders of magnitude, it is linear over a much wider range than the phosphorylase method. 

B31. Brewer, G. J., Bowbeer, D. R., and Tashian, R. E., The electrophoretic phenotypra of red cell phosphoglucomutase, adenylate kinase and acid phosphatase in the American Negro. Acta Genet. Statist. Med. 17, 97-103 (1967). 

CMP-N-acetylneuraminic acid (CMP-NeuAc). CMP-N-acetylneuraminic acid has been prepared enzymatically on small scales (> 0.5 mmol) from CTP and NeuAc, under catalysis by CMP-NeuAc synthetase (EC 2.7.7.43) [131l An improvement in this procedure, involving in situ production of CTP from CMP under adenylate kinase and pyruvate kinase catalysis, is suitable for multigram-scale synthesis11321. Adenylate kinase catalyzes the equilibration of CTP and CMP to CDP, which is subsequently phosphorylated by pyruvate kinase to provide CTP. A one-pot synthesis of CMP-NeuAc based on this procedure involves the in situ synthesis of NeuAc from N-acetylmannosamine and pyruvate, catalyzed by sialic acid aldolase (Fig. 11.3-12)[10S1. Chemical syntheses of CMP-NeuAc have also been reported11421. 

A conceptually similar approach can be used to determine the configurations of chiral phosphate monoesters of chiral alcohols without the necessity for transferring the chiral phosphoryl group to 1,3-butanediol. For example, in a number of stereochemical studies of hydrolysis reactions performed in the author s laboratory, 3 - or 5 -nucleotides were obtained as reaction products. In the case of samples of 5 -AMP, these can be enzymically converted to isotopically labeled cyclic 3, 5 -nucleotides by initial pyrophosphorylation with adenylate kinase and pyruvate kinase, followed by enzymic cyclization with inversion of configuration by a bacterial adenylate cyclase (20) (see Figs. 6 and 7). In the case of samples of 3 -nucleotides or 5 -nucleotides other than 5 -AMP, the cyclization reactions can be accomplished chemically (23). In either case, following chemical con-... 

Cleavage of RNA using nuclease P- yields a mixture of nucleoside monophosphates, contaminated with oligonucleotides and other materials. The AMP present in this mixture can be converted selectively to ATP by treatment with acetyl phosphate and a mixture of adenylate kinase and acetate kinase. The resulting mixture can be used directly, without purification to supply ATP for use in cofactor recycling. 

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