The intracellular distribution and diffusivity of adenosine triphosphate (ATP) was studied by cryomicrodissection of individual Rana pipiens oocytes. We measured ATP concentrations in the nucleus, in animal and vegetal hemisphere cytoplasm, and in an intracellular reference phase (iRP, a microinjected gelatin "organelle") which samples diffusive ATP. Regional concentrations were not equal: nucl...

Soluble amino acid incorporation systems from ascites tumor cells, as well as from regenerating rat liver, incorporated arginine into the protein fraction in the absence of ribosomes. This incorporation is dependent on transfer RNA, adenosine triphosphate, and adenosine triphosphate generator, but not on guanosine triphosphate or an amino acid mixture. The reaction is inhibited by puromycin and...

Woronick and Johnson (1) observed in Aspergillus niger extracts a pyruvate carboxylating system requiring adenosine triphosphate, but not involving phosphopyruvate, and suggested that the carboxylation reaction was coupled with the conversion of adenosine triphosphate to adenosine diphosphate and inorganic phosphate. Utter and Keech (2) studied a similar reaction in extracts of avian and beef l...

Two major species of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) differing in size, pyridine nucleotide specificity, and susceptibility to inhibition by adenosine 5'-triphosphate (ATP) were detected in extracts of Pseudomonas multivorans (which has recently been shown to be synonymous with the species Pseudomonas cepacia) ATCC 17616. The large species (molecular weight ca. 230,000) was acti...

Mycophenolic acid, an inhibitor of inosinate dehydrogenase, had cytostatic and cytotoxic effects on cultured neuroblastoma cells. Proliferation was inhibited by 50% when cells were incubated with 0.07 micrometerM mycophenolic acid, and cell viability was reduced by 83% when cells were treated with 10 micrometerM mycophenolic acid for 24 hr. Treatment of monolayer cultures with mycophenolic acid...

Mouse lymphoma L5178Y cells in culture were syn chronized by exposure to thymidine and Colcemid. At four times during the cell cycle, various aspects of purine metab olism were examined with the use of radioactive purine bases. In all experiments the uptake and conversion of bases to nucleotides was rate limiting for ribonucleoside triphosphate synthesis. Cell cycle variations in the apparent e...

The regulation of ATP metabolism by inorganic phosphate (Pi) was examined in five normal volunteers through measurements of ATP degradation during relative Pi depletion and repletion states. Relative Pi depletion was achieved through dietary restriction and phosphate binders, whereas a Pi-repleted state was produced by oral Pi supplementation. ATP was radioactively labeled by the infusion of 18...

Several laboratories have reported studies on individual enzymes that belong to the general class of adenosine triphosphate : nucleoside monophosphate phosphotransferases (EC 2.7.4.4), commonly termed nucleoside monophosphate kinases (l-7). Studies with partially purified enzyme preparations have indicated that a variety of nucleoside monophosphates can serve as alternative substrates for nucle...

Nucleic acids are among the most researched and applied biomolecules. Their diverse two- and three-dimensional structures in conjunction with their robust chemistry and ease of manipulation provide a rare opportunity for sensor applications. Moreover, their high biocompatibility has seen them being used in the construction of in vivo assays. Various nucleic acid-based devices have been extensiv...