Adenine phosphoribosyltransferase
Encyclopedia
Adenine phosphoribosyltransferase is an enzyme
that in humans is encoded by the APRT gene
.
involved in the purine
nucleotide salvage pathway. It functions as a catalyst in the reaction between adenine
and phosphoribosyl pyrophosphate
(PRPP) to form AMP
.
APRT is functionally related to hypoxanthine-guanine phosphoribosyltransferase
(HPRT).
beings may lead to kidney stones formed of adenine
and salts.
2,8-Dihydroxy-adenine urolithiasis
is also known as "adenine phosphoribosyltransferase deficiency".
Adenine phosphoribosyltransferase (APRT) deficiency is an uncommon genetic disorder that often causes kidney stones, and in some patients kidney failure. More than 300 individuals with this disease have been reported world-wide but it is not known how common this medical problem truly is. Patients with the disease deficiency lack the enzyme adenine phosphoribosyltransferase and therefore have difficulties breaking down dietary substances called purines, resulting in accumulation of a compound called 2,8-dihydroxyadenine (2,8-DHA) that is excreted by the kidneys. 2,8-DHA is poorly soluble in the urine leads to the formation of kidney stones and kidney injury. Interestingly, up to 70% of affected patients, have red hair or relatives with this hair color.
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that in humans is encoded by the APRT gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Function
APRTase is an enzymeEnzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
involved in the purine
Purine
A purine is a heterocyclic aromatic organic compound, consisting of a pyrimidine ring fused to an imidazole ring. Purines, including substituted purines and their tautomers, are the most widely distributed kind of nitrogen-containing heterocycle in nature....
nucleotide salvage pathway. It functions as a catalyst in the reaction between adenine
Adenine
Adenine is a nucleobase with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate and the cofactors nicotinamide adenine dinucleotide and flavin adenine dinucleotide , and protein synthesis, as a chemical component of DNA...
and phosphoribosyl pyrophosphate
Phosphoribosyl pyrophosphate
Phosphoribosyl pyrophosphate is a pentosephosphate.It is formed from ribose 5-phosphate by the enzyme ribose-phosphate diphosphokinase.It plays a role in transferring phospho-ribose groups in several reactions:...
(PRPP) to form AMP
Adenosine monophosphate
Adenosine monophosphate , also known as 5'-adenylic acid, is a nucleotide that is used as a monomer in RNA. It is an ester of phosphoric acid and the nucleoside adenosine. AMP consists of a phosphate group, the sugar ribose, and the nucleobase adenine...
.
APRT is functionally related to hypoxanthine-guanine phosphoribosyltransferase
Hypoxanthine-guanine phosphoribosyltransferase
Hypoxanthine-guanine phosphoribosyltransferase is an enzyme encoded in humans by the HPRT1 gene.HGPRT is a transferase that catalyzes conversion of hypoxanthine to inosine monophosphate and guanine to guanosine monophosphate. This reaction transfers the 5-phosphoribosyl group from...
(HPRT).
Pathology
Deficiency of APRT in humanHuman
Humans are the only living species in the Homo genus...
beings may lead to kidney stones formed of adenine
Adenine
Adenine is a nucleobase with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate and the cofactors nicotinamide adenine dinucleotide and flavin adenine dinucleotide , and protein synthesis, as a chemical component of DNA...
and salts.
2,8-Dihydroxy-adenine urolithiasis
2,8 dihydroxy-adenine urolithiasis
Adenine phosphoribosyltransferase deficiency is an autosomal recessive metabolic disorder associated with a mutation in the enzyme adenine phosphoribosyltransferase....
is also known as "adenine phosphoribosyltransferase deficiency".
Adenine phosphoribosyltransferase (APRT) deficiency is an uncommon genetic disorder that often causes kidney stones, and in some patients kidney failure. More than 300 individuals with this disease have been reported world-wide but it is not known how common this medical problem truly is. Patients with the disease deficiency lack the enzyme adenine phosphoribosyltransferase and therefore have difficulties breaking down dietary substances called purines, resulting in accumulation of a compound called 2,8-dihydroxyadenine (2,8-DHA) that is excreted by the kidneys. 2,8-DHA is poorly soluble in the urine leads to the formation of kidney stones and kidney injury. Interestingly, up to 70% of affected patients, have red hair or relatives with this hair color.