NAD+kinase

Ruiz, J.M. et ah. Proline metabolism and NAD kinase activity in green bean plants subjected to cold shock. Phytochemistry, 59, 473, 2002. 

Mata R, Gamboa A, Macias M, Santillan S, UUoa M, Gonzalez MC, Effect of selected phytotoxic agents from Guanomyces polythrix on the calmodulin-dependent activity of the enzymes cAMP phosphodiesterase and NAD-kinase, JAgricFood Chem 51 4559 562, 2003. 

MEVALONATE KINASE MYOSIN and MYOSIN ATPase NAD KINASE NAD SYNTHETASE... 

NADH PEROXIDASE NADH PEROXIDASE NAD KINASE NAD nucleosidase,... 

The release of Ca2+ in response to such second messengers is known to activate the phosphorylation of a range of cytosolic proteins by Ca2+-dependent protein kinases, for example in hepatocytes,417 adrenal cortex418 and other cells.419 Ca2+ inhibits cAMP-activated protein kinase in parathyroid glands.420 Phosphorylation of proteins produced in the pancreatic /8-cell in response to enhanced [Ca2+] may involve calmodulin, while the stimulus produced by glucose is potentiated by cAMP 421 A calmodulin-activated NAD kinase is present in the outer mitochondrial membrane of com.422... 

Nine submicromolar inhibitors were found. Additional further docking for NAD kinase inhibitors found that 22 showed activity versus NAD synthetase and one against NAD kinase out of 100 compounds tested... 

It has been established that in some bacteria one enzyme displays both activities (Kawai et al., 2000). An enzyme with both PolyP- and ATP-dependent NAD kinase activities was isolated from Micrococcus flavus. This enzyme is a dimer consisting of 34 kDa subunits. A gene Rvl 695 has been found in Mycobacterium tuberculosis and proposed to also be a PolyP-dependent NAD kinase. By cloning and expression in E. coli, Rvl695 was shown to encode PolyP/ATP-NAD kinase and was named as ppnk. The ppnk product, a recombinant PolyP/ATP-NAD kinase (Ppnk), was purified and characterized. This enzyme was a tetramer consisting of 35 kDa sub-units when expressed in E. coli. PolyP/ATP-NAD kinases of M. flavus and Ppnk of M. tuberculosis H37Rv phosphorylated NAD, using PolyP and nucleoside triphosphates as the phosphoryl donors (Kawai et al., 2000). 

Figure 6.7 Enzymes coupling metabolism of PolyPs and nucleoside phosphates in bacteria (1) polyphosphate kinases (2) glucokinases (3) NAD kinases (4) PolyP AMP phosphotransferase (5) adenylate kinase.

It should be noted that many PolyP-dependent enzymes (polyphosphate kinase, exopolyphosphatases, PolyP glucokinase and NAD kinase) are multifunctional and can catalyse reactions both with PolyPs and nucleotide triphosphates. Some PolyP-dependent enzymes, especially exopolyphosphatases, provide excellent examples of cell-compartment specific enzymes. Cell-compartment specificity is a characteristic feature of eucaryotic ATPases (Nelson, 1992) and pyrophosphatases (Baltscheffsky and Baltscheffsky, 1992 Davies et al, 1997 Baykov et al, 1999). This means that the same reaction may be performed in cell compartments by specific enzymes, which differ in their properties, encoding genes and functions. All of the above properties of PolyP-dependent enzymes suggest their important role in the regulation of living cell functions as a whole. 

In many prokaryotes, PolyP is a direct phosphorus donor for biochemical reactions due to the action of enzymes such as polyphosphate-glucose phosphotransferase and NAD kinase. Polyphosphate kinases and PolyP AMP phosphotransferase link nucleoside-polyphosphate and inorganic PolyP. Polyphosphate kinases 1 and 2 can use PolyPs for the synthesis of different nucleoside triphosphates. 

S. Kawai, S. Mori, T. Mukai, S. Suzuki, T. Yamada, W. Hashimoto and K. Murata (2000). Inorganic Polyphosphate/ATP-NAD kinase of Micrococcus flavus and Mycobacterium tuberculosis H37Rv. 

NADP+ is derived from NAD+ by phosphorylation of the 2 -hydroxyl group of the adenine ribose moiety. This transfer of a phosphoryl group from ATP is catalyzed by NAD kinase. 

Roberts, D. M Rowe, P. M Siegel, F. L Lukas, T. J Watterson, D. M. (1986). Trimethyllysine and protein function effect of methylation and mutagenesis of lysine 115 of calmodulin on NAD kinase activation. J. Biol. Chem. 261,1491-1494. 

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