Biomaterial Database

Stimulation of adenine phosphoribosyltransferase by adenosine triphosphate and other nucleoside triphosphates. 1967

A W Murray, and P C Wong

1. Adenine phosphoribosyltransferase was protected from inactivation on heating at 55 degrees by the presence of 5-phosphoribosyl pyrophosphate. ATP, adenine, AMP or GMP had no protective effect on the activity of this enzyme. The presence of either 5-phosphoribosyl pyrophosphate or ATP did not protect adenine phosphoribosyltransferase against the loss of ATP stimulation obtained by heating at 55 degrees . 2. At pH5.3 and 6.0 adenine phosphoribosyltransferase was stimulated by a narrow range of ATP concentration (15-25mum). At pH6.5 and 7.0 maximum stimulation was obtained with 25-30mum-ATP, and at pH7.4, 8.2 and 8.85 maximum stimulation was obtained over a wide range of ATP concentrations (60-200mum). With extracts that had been heated for 30min. at 55 degrees no stimulation was observed at either pH5.3 or 7.4 with ATP concentrations up to 100mum. 3. Short periods of heating at 55 degrees (1, 2 or 5min.) increased the stimulation of adenine phosphoribosyltransferase obtained with various concentrations of ATP. 4. The addition of CTP, GTP, deoxy-GTP, deoxy-TTP or XTP to assay mixtures resulted in weak stimulation of adenine-phosphoribosyltransferase activity. 5. It is suggested that there are at least three different forms of adenine phosphoribosyltransferase, each with a different affinity for ATP.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009711	Nucleotides	The monomeric units from which DNA or RNA polymers are constructed. They consist of a purine or pyrimidine base, a pentose sugar, and a phosphate group. (From King & Stansfield, A Dictionary of Genetics, 4th ed)	Nucleotide
D002286	Carcinoma, Ehrlich Tumor	A transplantable, poorly differentiated malignant tumor which appeared originally as a spontaneous breast carcinoma in a mouse. It grows in both solid and ascitic forms.	Ehrlich Ascites Tumor,Ascites Tumor, Ehrlich,Ehrlich Tumor Carcinoma,Tumor, Ehrlich Ascites
D005964	Glucosyltransferases	Enzymes that catalyze the transfer of glucose from a nucleoside diphosphate glucose to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.-.	Glucosyltransferase
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000255	Adenosine Triphosphate	An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.	ATP,Adenosine Triphosphate, Calcium Salt,Adenosine Triphosphate, Chromium Salt,Adenosine Triphosphate, Magnesium Salt,Adenosine Triphosphate, Manganese Salt,Adenylpyrophosphate,CaATP,CrATP,Manganese Adenosine Triphosphate,MgATP,MnATP,ATP-MgCl2,Adenosine Triphosphate, Chromium Ammonium Salt,Adenosine Triphosphate, Magnesium Chloride,Atriphos,Chromium Adenosine Triphosphate,Cr(H2O)4 ATP,Magnesium Adenosine Triphosphate,Striadyne,ATP MgCl2
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia