Formation of hydroxypyruvaldehyde phosphate in human erythrocytes

Human erythrocytes when incubated with [U-14C]glucose formed radioactively labeled hydroxypyruvaldehyde-P (CHOCOCH2OPO3(2-)). Using a "diagonal" chromatographic procedure on an anion exchange column for isolation and quantitative detection, up to 0.3 mumol of hydroxypyruvaldehyde-P/liter of packed cells was found. If glycolysis was blocked by inhibition of glyceraldehyde-3-P dehydrogenase with N-ethylmaleimide and iodoacetate, 0.7 mumol of hydroxypyruvaldehyde-P/liter of packed erythrocytes was detected. Hydroxypyruvaldehyde-P, found for the first time in eukaryotic cells, might be one of the long sought natural substrates of the glyoxalases.