L-ornithine transaminase synthesis in Saccharomyces cerevisiae: Regulation by inducer exclusion

  title={L-ornithine transaminase synthesis in Saccharomyces cerevisiae: Regulation by inducer exclusion},
  author={Jacqueline Deschamps and Evelyne Dubois and J. M. Wiame},
  journal={Molecular and General Genetics MGG},
SummaryThe ornithine transaminase (EC. of Saccharomyces cerevisiae is induced by arginine, ornithine, and their analogs. Genetic regulatory elements which are involved in this induction process have been defined due to the isolation of specific mutants. Two classes of OTAse operator mutants have previously been described; three unlinked genes are presumed to code for a specific repressor, CARGR of both of the arginine catabolic enzymes, arginase, and ornithine transaminase. The level… Expand
Induction and derepression of arginase and ornithine transaminase in different strains ofSaccharomyces cerevisiae
Extracellular steady-state arginine concentrations higher than about 0.1mm, in addition to abundant energy supply, were found to be required for high production of arginase, and it is suggested that, besides intracellularArginine, extracellular Arginine may provide an induction signal necessary for full-scale induction of Arginase synthesis. Expand
L-ornithine transaminase synthesis in Saccharomyces cerevisiae: Induction by allophanate, intermediate and inducer of the urea degradative pathway adds to arginine induction
Yeast ornithine transaminase is shown to be subject to a second induction circuit, that which is responsible for urea amidolyase and urea permease induction by allophanate and defined by the regulatory mutants durL− and durM−. Expand
Positive and negative regulation ofCAR1 Expression inSaccharomyces cerevisiae
Fusion tolacZ of several fragments of the 5′ non-coding region showed that induction ofCAR1 by arginine is positively regulated by the products of theARGR genes, and the order of the regulatory regions was confirmed: 5′—nitrogen catabolite repression—activation byArginine—CARGRI-mediated repression—CAR1. Expand
Regulation of Amino Acid, Nucleotide, and Phosphate Metabolism in Saccharomyces cerevisiae
This review focuses on recent developments in the field of amino acid, nucleotide, and phosphate metabolism and provides illustrative examples of how yeast cells combine a variety of mechanisms to achieve coordinated regulation of multiple metabolic pathways. Expand


The participation of ornithine and citrulline in the regulation of arginine metabolism in Saccharomyces cerevisiae.
The pools of arginine, ornithine and citrulline have been measured under different conditions of growth in wild type and argR mutants (non-repressible for ornithine transcarbamylase and four otherExpand
Specific induction of catabolism and its relation to repression of biosynthesis in arginine metabolism of Saccharomyces cerevisiae.
Abstract Experimental results are presented in support of the model previously proposed for specific induction of the synthesis of enzymes for arginine catabolism in Saccharomyces cerevisiae ( Wiame,Expand
The Regulation of Arginine Metabolism in Saccharomyces cerevisiae: Exclusion Mechanisms
Publisher Summary This chapter discusses arginine biosynthesis and degradation in Saccharomyces cerevisiae ( S . cerevisiae ). S . cerevisiae is able to make its own arginine from ammonium as soleExpand
Mutations affecting the repressibility of arginine biosynthetic enzymes in Saccharomyces cerevisiae.
A method is described for isolating mutants of Saccharomyces cerevisiae which have lost repressibility by exogenous arginine for ornithine transcarbamylase and three complementary classes of mutations were found: argRI, argRII and argRIII which are recessive and define three loci. Expand
The participation of the anabolic glutamate dehydrogenase in the nitrogen catabolite repression of arginase in Saccharomyces cerevisiae.
It is shown that controversial conclusions can be reached when using different approaches to provoke catabolite derepression, and it becomes possible to show that additional regulatory processes are involved in arginase sythesis. Expand
Mating-type effect on cis mutations leading to constitutivity of ornithine transaminase in diploid cells of Saccharomyces cerevisiae.
Two different types of mutations have been recovered that affect L-ornithine transaminase (OTAse), an enzyme catalyzing the second step of arginine breakdown in yeast, both of which are tightly linked to the structural gene (cargB) for this enzyme. Expand
Isolation and Characterization of Methylammonium-resistant Mutants of Saccharomyces cerevisiae with Relieved Nitrogen Metabolite Repression of Allantoinase, Arginase and Ornithine Transaminase Synthesis
The allNMR locus may have a general function in nitrogen metabolite repression of various degradative pathways since the allNmr mutation causes resistance to methylammonium in the presence of several metabolically unrelated nitrogen sources. Expand
Interaction between arginase and L-ornithine carbamoyltransferase in Saccharomyces cerevisiae. Purification of S. cerevisiae enzymes and evidence that these enzymes as well as rat-liver arginase are trimers.
The data suggest that the 1-to-1 regulatory complex of ornithine carbamoyltransferase and arginase of S. cerevisiae, leading to ornithin carbamoysl transferase inhibition, is an hexamer. Expand
Interaction between Arginase and Ornithine Carbamoyltransferase
The inhibition of ornithine carbamoyltransferase by arginase in Saccharomyces cerevisiae, which is under the control of arginine and ornithine, involves a regulatory site on the ornithineExpand
Catabolic synergism. A cooperation between the availability of substrate and the need for nitrogen in the regulation of arginine catabolism in Saccharomyces cerevisiae
cargA+Oh mutation allows to make further distinction between the promotion of arginase synthesis caused by nitrogen limitation and nitrogen starvation. Expand