Hypoxanthine-guanine phosphoribosyltransferase from rat liver. Effects of magnesium 5-phosphoribosyl 1-pyrophosphate on the chemical modification and stability of the enzyme.

  title={Hypoxanthine-guanine phosphoribosyltransferase from rat liver. Effects of magnesium 5-phosphoribosyl 1-pyrophosphate on the chemical modification and stability of the enzyme.},
  author={Y Natsumeda and Masataka Yoshino and Keizo Tsushima},
  journal={Biochimica et biophysica acta},
  volume={483 1},
7 Citations
Evidence against the existence of real isozymes of hypoxanthine phosphoribosyltransferase.
It is suggested that the use of the term 'isozyme' to describe the different forms of hypoxanthine phosphoribosyltransferase should be avoided and the native enzymes mainly have a molecular weight of 105000--110000 and are thus apparently tetrameric, when held in the active state by the presence of phosphorIBosyl diphosphate.
De novo guanylate synthesis in the commitment to replication in hepatoma 3924A cells.
A striking redirection in the distribution of label from IMP utilization to the preferential synthesis of guanylates during the expression of the biochemical proliferative program of cancer cells supports the potential significance of this pathway as a target of chemotherapy.
The effect of phosphoribosylpyrophosphate on stability and configuration of hypoxanthineguaninephosphoribosyltransferase and adeninephosphoribosyltransferase from human erythrocytes.
PRPP stabilizes these purine phosphoribosyltransferases against thermal inactivation in vitro and using sucrose density gradient ultracentrifugation investigated whether this stabilisation is associated with a change in the configuration of these enzymes.
Structural Features of the Phosphoribosyl-Transferases and Their Relationship to the Human Deficiency Disorders of Purine and Pyrimidine Metabolis
It is proposed that metabolic diseases of purine and pyrimidine metabolism are the consequence of structural mutations to an architectural domain common to all of the phosphoribosyltransferases.


Human hypoxanthine phosphoribosyltransferase. I. Purification, properties, and specificity.
Kinetic studies of magnesium effects are consistent with the view that magnesium activates nucleotide synthesis by complexing with the substrates 5-phosphoribosyl 1-pyrophosphate and 5-aminoimidazole-4-carboxamide.
Human hypoxanthine phosphoribosyltransferase. II. Kinetics and chemical modification.
Preliminary treatment of the enzyme with PP-ribose-P resulted in an initial burst of IMP synthesis when hypoxanthine was added, and PPi was an effective inhibitor at low magnesium sulfate concentrations but an ineffective inhibitor at high levels of this salt.
Chinese hamster hypoxanthine-guanine phosphoribosyltransferase. Purification, structural, and catalytic properties.
Abstract Hypoxanthine-guanine phosphoribosyltransferase from Chinese hamster brain, liver, and V79 tissue culture cells appears to have identical structural and catalytic properties. The enzyme has
The regional distribution of HGPRTase activity in adult rat brain is more homogenous than that reported for human brain and the enzyme is predominantly a constituent of the soluble supernatant fraction, but can also be found in carefully washed synaptosomes.
Abnormal Property of Human Mutant Hypoxanthine‐Guanine Phosphoribosyltransferase: Insensitivity of Fibroblast Enzyme to Stabilization against Freezing and Thawing by 5‐Phosphoribosyl‐1‐Pyrophosphate
The insensitivity of the mutant HGPRT from the patient with partial enzyme deficiency to PRPP stabilization indicates a structural enzyme alteration, and the different sensitivity of the two HG PRT mutants toPRPP stabilization reflects the heterogeneity of HGPRt mutations in man.
Human hypoxanthine-guanine phosphoribosyltransferase. Purification and subunit structure.
Hypoxanthine-guanine phosphoribosyltransferase has been purified to homogeneity from human erythrocytes obtained from one male donor and electrophoretic heterogeneity appears to result from a nongenetic, post-transcriptional alteration of one or both subunits.
The measurement of amino groups in proteins and peptides.
  • R. Fields
  • Chemistry, Biology
    The Biochemical journal
  • 1971
A technique is examined for determining amino groups with 2,4,6-trinitrobenzenesulphonic acid, in which the extinction at 420nm of sulphite complexes of the trinitrophenylated amino groups is measured, and the reaction with several amino acids, peptides and proteins is presented.