Disease relevance of TAL1

• From a genetic point of view, it is well known that several micro-organisms, including Escherichia coli and S. cerevisiae, contain multiple genes encoding isoenzymes of transketolase and transaldolase [1].

High impact information on TAL1

• This also applies to transketolase, transaldolase and fructose-1,6-bisphosphatase [2].
• In the presence of hexacyanoferrate(III) transaldolase thus functions as an efficient catalyst of the oxidative cleavage of its donor substrates fructose-6-P or sedoheptulose-7-P into hydroxypyruvaldehyde and glyceraldehyde-3-P or erythrose-4-P, respectively [3].
• The transaldolase-dihydroxyacetone carbanion intermediate formed in the reaction of transaldolase with its donor substrates fructose-6-P or sedoheptulose-7-P is susceptible to oxidation by hexacyanoferrate(III) [3].
• Oxidation of the carbanion intermediate of transaldolase by hexacyanoferrate (III) [3].
• We have isolated the gene encoding transaldolase from Kluyveromyces lactis (KITAL1) by screening a genomic library of this yeast using the TAL1 gene of Saccharomyces cerevisiae as a radioactive probe [4].

Biological context of TAL1

• This plasmid contained an open reading frame (ORF) designated PsTAL1 based on a high level of homology with S. cerevisiae TAL1 [5].
• TAL1 is not an essential gene [6].
• Transformants carrying the TAL1 gene on a multicopy plasmid over-produced transaldolase [6].

Anatomical context of TAL1

• In addition, transketolase, transaldolase, and glucose-6-phosphatase, a known cisternal enzyme, are inactivated by chymotrypsin and subtilisin only in disrupted hepatic microsomes under conditions in which NADPH-cytochrome c reductase, an enzyme on the external surface, is inactivated equally in intact and disrupted microsomes [7].

Associations of TAL1 with chemical compounds

• A XYL1- and XYL2-containing S. cerevisiae strain overexpressing TAL1 (S104-TAL) showed considerably enhanced growth on xylose compared with a strain containing only XYL1 and XYL2 [8].
• Fermentation of the recombinant S. cerevisiae strains containing XYL1, XYL2, TKL1, and TAL1 were studied with mixtures of glucose and xylose [9].
• However, the specific growth rate on xylulose increased from 0.02-0.03 for TMB3001 to 0.12 for the strain overproducing only transaldolase (TAL1) and to 0.23 for TMB3026, suggesting that overproducing all four enzymes has a synergistic effect [10].
• Activities of the key enzymes in the pentose phosphate pathway (transketolase, transaldolase) increased 2-fold while the concentrations of their substrates (pentose 5-phosphates, sedoheptulose 7-phosphate) decreased correspondingly [11].
• Moreover, high L-arabinose uptake rates and enhanced transaldolase activities favor utilization of L-arabinose [12].

Other interactions of TAL1

• Pentose-phosphate pathway in Saccharomyces cerevisiae: analysis of deletion mutants for transketolase, transaldolase, and glucose 6-phosphate dehydrogenase [13].
• In order to enhance xylose utilisation in the XYL1-, XYL2-containing S. cerevisiae strains, the native genes encoding transketolase and transaldolase were also overexpressed [14].
• Mutants lacking both transaldolase and phosphoglucose isomerase grew more slowly than the single mutants [6].

Analytical, diagnostic and therapeutic context of TAL1

• Furthermore, both transaldolase isoenzymes which were detected in wild-type crude extracts by immunoblotting were missing in the deletion mutants [6].

References