86-04-4Relevant articles and documents
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Webster
, p. 453 (1953)
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Dual activity of certain HIT-proteins: A. thaliana Hint4 and C. elegans DcpS act on adenosine 5′-phosphosulfate as hydrolases (forming AMP) and as phosphorylases (forming ADP)
Guranowski, Andrzej,Wojdyla, Anna Maria,Zimny, Jaroslaw,Wypijewska, Anna,Kowalska, Joanna,Jemielity, Jacek,Davis, Richard E.,Bieganowski, Pawel
experimental part, p. 93 - 98 (2010/12/18)
Histidine triad (HIT)-family proteins interact with different mono- and dinucleotides and catalyze their hydrolysis. During a study of the substrate specificity of seven HIT-family proteins, we have shown that each can act as a sulfohydrolase, catalyzing the liberation of AMP from adenosine 5′-phosphosulfate (APS or SO4-pA). However, in the presence of orthophosphate, Arabidopsis thaliana Hint4 and Caenorhabditis elegans DcpS also behaved as APS phosphorylases, forming ADP. Low pH promoted the phosphorolytic and high pH the hydrolytic activities. These proteins, and in particular Hint4, also catalyzed hydrolysis or phosphorolysis of some other adenylyl-derivatives but at lower rates than those for APS cleavage. A mechanism for these activities is proposed and the possible role of some HIT-proteins in APS metabolism is discussed.
Nucleoside-Triphosphatase Activity of an ATP-Dependent Enzyme, N-Methylhydantoin Amidohydrolase
Ogawa, Jun,Nirdnoy, Warawadee,Yamada, Hideaki,Shimizu, Sakayu
, p. 1737 - 1739 (2007/10/02)
N-Methylhydantoin amidohydrolase, which catalyzes ATP-dependent hydrolysis of N-methylhydantoin to N-carbamoylsarcosine, was found to hydrolyze several nucleoside triphosphates to nucleoside diphosphates not only in the presence but also in the absence of amide substrates.Amide substrates, such as N-methylhydantoin and dihydrouracil, seem to be absolutely necessary for hydrolysis of ATP and dATP.However, N-methylhydantoin inhibited the hydrolysis of nucleoside triphosphates other than ATP and dATP.The kinetic data suggest that the presence of an amide substrate changes the affinity of the enzyme toward nucleoside triphosphates.