High impact information on GLO1

• Methylglyoxal is also synthesized from dihydroxyacetone phosphate; therefore, induction of the GLO1 gene expression by osmotic stress was thought to scavenge methylglyoxal, which increased during glycerol production for adaptation to osmotic stress [1].
• Detoxification of methylglyoxal is performed by glyoxalase I. Expression of the structural gene of glyoxalase I (GLO1) of Saccharomyces cerevisiae under several stress conditions was investigated using the GLO1-lacZ fusion gene, and expression of the GLO1 gene was found to be specifically induced by osmotic stress [1].
• The gsh2-deficient mutant, which accumulates gamma-glutamylcysteine (an intermediate of glutathione biosynthesis), was also sensitive to methylglyoxal compared with the isogenic wild type strain, although the growth arrest caused by methylglyoxal was partially restored by overexpression of the GLO1 gene [2].
• Glyoxalase I activity increased approximately 95-fold when the GLO1 gene was introduced into the yeast cell with a multicopy plasmid, and the resultant transformant showed the increased resistance against methylglyoxal [2].
• Since the knockout mutant of the GLO1 gene of haploid strain of S. cerevisiae was still viable, the GLO1 gene was thought to be unnecessary for growth of the yeast [2].

Biological context of GLO1

• The GLO1 gene contained an open reading frame with 326 amino acids, and the molecular weight of the gene product (Glo1p) deduced from the DNA sequence was calculated to be 37,207.06 [2].
• Glyoxalase-I activity and cell cycle regulation in yeast [3].
• Results demonstrate that although glyoxalase-I activity is a good indicator of cell growth status, it is not involved in cell cycle regulation of this eukaryotic organism [3].
• In one of these mutants, which showed a specific morphological phenotype, the tagged gene, glo1 , was found to encode a product that is highly homologous to a glyoxal oxidase gene from the wood-rot fungus Phanerochaete chrysosporium [4].

Associations of GLO1 with chemical compounds

• Glyoxalase I (lactoylglutathione lyase, EC 4.4.1.5) converts the hemithiolacetal of glutathione and an alpha-ketoaldehyde to S-D-lactoylglutathione which is hydrolysed under the catalytic influence of glyoxalase II to produce D-lactate and regenerate glutathione [5].
• Using a Glo1-overproducing strain we demonstrated that Glo1 is membrane bound, oxidizes a series of small aldehydes (< C4) and produces H2O2 [4].

Other interactions of GLO1

• A sudden overaccumulation of methylglyoxal (MG) induces, in Saccharomyces cerevisiae, the expression of MG-protective genes, including GPD1, GLO1 and GRE3 [6].
• Nitrosative stress on yeast: inhibition of glyoxalase-I and glyceraldehyde-3-phosphate dehydrogenase in the presence of GSNO [7].

References