The activities of six bacteriophage T2r+-induced enzymes (thymidylate synthetase, deoxycytidylate deaminase, thymidylate kinase, deoxycytidylate hydroxymethylase, deoxycytidine pyrophosphatase, and dihydrofolate reductase) were measured after dilution of phage-infected Escherichia coli B from 8 X 108 to 2 x 108 cells per ml. The only enzyme activity altered was that of deoxycytidylate deaminase...

Glutaraldehyde-fixed membranes from rabbit kidney cortex were used to characterize binding of monomeric adenosine deaminase to the adenosine deaminase complexing protein. With the use of bovine adenosine deaminase it was shown that enzyme binding is a saturable, high affinity process. The K value for binding of the bovine enzyme was 11 nM. Maximum enzyme binding and rate of binding to a constan...

OBJECTIVES The relationship between adenosine deaminase and various cancers has been investigated in several studies. However, serum adenosine deaminase activity and carbonic anhydrase and catalase activities in patients with bladder cancer have not previously been reported. Therefore, the aim of this study was to measure serum adenosine deaminase, carbonic anhydrase and catalase activities in ...

Adenosine deaminase deficiency accounts for approximately 15-20% of severe combined immunodeficiency in humans. The gene for adenosine deaminase is located on chromosome 20q12-q13.11 and codes for an aminohydrolase that catalyzes the deamination of adenosine and deoxyadenosine to inosine and deoxyinosine, respectively. Absence of the enzyme causes a build-up of the substrates in addition to exc...

We employed intracoronary infusion of adenosine deaminase to test the hypothesis that endogenous adenosine contributes to regulation of coronary blood flow following acute reductions in coronary artery pressure. In 16 closed-chest anesthetized dogs, we perfused the left circumflex coronary artery from a pressurized arterial reservoir and measured coronary blood flow following changes in perfusi...

1-Aminocyclopropane-1-carboxylate (ACC) deaminase-mediated reduction of ethylene generation in plants under abiotic stresses is a key mechanism by which bacteria can promote plant growth. Misidentification of ACC deaminase and the ACC deaminase structure gene (acdS) can lead to overestimation of the number of bacteria containing ACC deaminase and their function in ecosystems. Previous non-speci...

The gene encoding melamine deaminase (TriA) from Pseudomonas sp. strain NRRL B-12227 was identified, cloned into Escherichia coli, sequenced, and expressed for in vitro study of enzyme activity. Melamine deaminase displaced two of the three amino groups from melamine, producing ammeline and ammelide as sequential products. The first deamination reaction occurred more than 10 times faster than t...

30 Schizophrenia is characterized by pathophysiological alterations of multiple neurotransmitter 31 systems such as dopaminergic, glutamatergic, GABA-ergic and serotonergic pathways. 32 Adenosine, a homeostatic neuromodulator that mediates signaling through multiple 33 neurotransmitter pathways, is an emerging candidate neurobiological substrate of 34 schizophrenia. The present study examined p...

The binding of purified human erythrocyte AMP deaminase to human erythrocyte membranes and the effect of binding on enzyme catalytic activity was investigated. AMP deaminase binds preferentially and specifically to the cytoplasmic surface of the erythrocyte membrane. The binding is saturable, reversible, and responsive to alterations of pH, of ionic strength, and of ATP and AMP concentrations. ...

hepatocyte DNA synthesis, inhibited tryptophan oxygenase induction, and stimulated AMP deaminase activity. Simul taneous administration of ethionine with thioacetamide inhibited DNA synthesis. AMP deaminase activity was not stimulated appreciably during liver regeneration, and the modest changes recorded could not be readily attributed to hepatocyte DNA synthesis or mitosis. The relationship be...