Ultrastructural studies of rats or mice treated for 24 hr with a toxic dose (100 mg/kg) of methylglyoxal-bis(guanylhydrazone) revealed the presence of damaged mitochondria in the crypt cells of the intestinal epithelium. Mitochondria were severely swollen and electron lucent, and appeared to be similar to those observed previously in a variety of cell types treated in vitro and in vivo with met...

[1] We construct global budgets of atmospheric glyoxal and methylglyoxal with the goal of quantifying their potential for global secondary organic aerosol (SOA) formation via irreversible uptake by aqueous aerosols and clouds. We conduct a detailed simulation of glyoxal and methylglyoxal in the GEOS-Chem global 3-D chemical transport model including our best knowledge of source and sink process...

Protein glycation by methylglyoxal is a nonenzymatic post-translational modification whereby arginine and lysine side chains form a chemically heterogeneous group of advanced glycation end-products. Methylglyoxal-derived advanced glycation end-products are involved in pathologies such as diabetes and neurodegenerative diseases of the amyloid type. As methylglyoxal is produced nonenzymatically f...

A gene encoding a putative 150-amino-acid methylglyoxal synthase was identified in Clostridium acetobutylicum ATCC 824. The enzyme was overexpressed in Escherichia coli and purified. Methylglyoxal synthase has a native molecular mass of 60 kDa and an optimum pH of 7.5. The Km and Vmax values for the substrate dihydroxyacetone phosphate were 0.53 mM and 1.56 mmol min(-1) microgram(-1), respectiv...

B11 ( o1tmuox It. \IcKIXXEY AND SAMUEL P. MARTIN N MECHANISM is known for the reaction whereby normal polymorphomiuclear leukocytes have the capa(’ity to form relatively large quantities of lactic acid in the presemice of oxygen) Since leukoc’ytes fromu healthy imi(lividuals comitaimi an active glyoxalase system,2 methylglyoxal may serve as a possible precursor of this lactic acid. Levene and M...

The role of the tripeptide glutathione in the growth and survival of Escherichia coli cells has been investigated. Glutathione-deficient mutants leak potassium and have a reduced cytoplasmic pH. These mutants are more sensitive to methylglyoxal than the parent strain, indicating that in the absence of glutathione-dependent detoxification, acidification of the cytoplasm cannot fully protect cell...

The dicarbonyl compound methylglyoxal is a natural constituent of Manuka honey produced from Manuka flowers in New Zealand. It is known to possess both anticancer and antibacterial activity. Such observations prompted to investigate the ability of methylglyoxal as a potent drug against multidrug resistant Pseudomonas aeruginosa. A total of 12 test P. aeruginosa strains isolated from various hos...

The posttranslational modification of proteins by methylglyoxal, a highly reactive compound derived from glycolysis, may contribute to aging, diabetes, and other disorders. In this issue of Cell, Brownlee and colleagues (Yao et al., 2006) demonstrate a specific mechanism by which methylglyoxal modifies a transcriptional corepressor to enhance gene expression.

Dicarbonyl and oxidative stress may play important roles in the development of diabetes complications, and their response to hyperglycemia could determine individual susceptibility to diabetic nephropathy. This study examines the relationship of methylglyoxal, 3-deoxyglucosone (3DG), and oxidative stress levels to diabetic nephropathy risk in three populations with diabetes. All subjects in the...

The substrate specificities of human aldose reductase and aldehyde reductase toward trioses, triose phosphates, and related three-carbon aldehydes and ketones were evaluated. Both enzymes are able to catalyze the NADPH-dependent reduction of all of the substrates used. Aldose reductase shows more discrimination among substrates than does aldehyde reductase and is generally the more efficient ca...