... effects of such treatment onisoaspartate formation, by measuring the levels of mem-brane protein methyl esters by the in situ methylation assay.PK activity was also measured in parallel, to assess ... G6PD-deficient ery-throcytes, damaged residues are significantly increased inmembrane proteins, in parallel with the decay of pyruvatekinase activity, used as a cell age marker. Erythrocytes frompatients ... andhaemolysis has not been unequivocally elucidated. AmongG6PD-deficient erythrocytes, aged cells are the mostsensitive to haemolysis, because of age-dependent decay of the activity of several enzymes,...