Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:O15067 (FGAM synthetase)
 19 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The assignment of the known ade genes to steps in purine biosynthesis in Schizosaccharomyces pombe has been completed with the demonstration that an ade3 mutants lacks FGAR amidotransferase, ade1A mutants lack GAR synthetase and ade1B mutants lack AIR synthetase. A comparison of enzyme activity with map position for ade1 mutants shows that (1) complementing ade1A mutants lack GAR synthetase but posses wild type amounts of AIR synthetase, (2) complementing ade1B mutants lack AIR synthetase but posses variable amounts of GAR synthetase, (3) non-complementing mutants lack both activities. In wild type strains the two activities fractionate together throughout a hundred-fold purification. Hence the ade1 gene appears to code for a bifunctional enzyme catalysing two distinct steps in purine biosynthesis. The two activities are catalysed by two different regions of the polypeptide chain which can be altered independently by mutation. Gel filtration studies on partially purified enzymes from wild type and various complementing mutant strains, indicate that the bifunctional enzyme is a multimer consisting of between four and six sub-units of 40,000 daltons each. GAR synthetase activity is associated with both the monomeric and multimeric forms but AIR synthetase is only associated with the multimer. A comparison of enzyme levels between diploids and their original complementing haploid strains suggests that complementation is due to hybrid enzyme formation.
Mol Gen Genet 1976 Sep 23
PMID:The product of the ade1: gene in Schizosaccharomyces pombe: a bifunctional enzyme catalysing two distinct steps in purine biosynthesis. 96 58

Extensive circadian (daily) control over gene expression in the cyanobacterium Synechococcus sp. strain PCC 7942 is programmed into at least two differentially phased groups. The transcriptional activity of the smaller group of genes is maximal at about dawn and minimal at about dusk. We identified one of the genes belonging to this latter group as purF, which encodes the key regulatory enzyme in the de novo purine synthetic pathway, glutamine PRPP amidotransferase (also known as amidophosphoribosyltransferase). Its expression pattern as a function of circadian time was confirmed by both luminescence from a purF::luxAB reporter strain and the abundance of purF mRNA. By fusing sequences upstream of the purF coding region to promoterless luxAB genes, we identified a limited upstream region, which potentially regulates purF circadian expression patterns in vivo. We also identified the purL gene immediately upstream of purF. The purL gene encodes FGAM synthetase, the fourth enzyme in the purine nucleotide biosynthesis pathway. Although these genes are expressed as part of a larger operon in other bacteria, reporter gene fusions revealed that purF and purL are transcribed independently in Synechococcus and that they are expressed at different phases of the circadian cycle. This differential expression pattern may be related to the oxygen sensitivity of amidophosphoribosyltransferase.
Mol Microbiol 1996 Jun
PMID:Circadian expression of genes involved in the purine biosynthetic pathway of the cyanobacterium Synechococcus sp. strain PCC 7942. 880 59