REAPPRAISAL OF P-31 NMR-STUDIES INDICATING ENZYME COMPLEXATION IN RED BLOOD-CELLS

31P NMR and column fractionation studies do not substantiate the existence in solution of a complex of phosphoglycerate kinase and phosphoglycerate mutase or of one involving these enzymes and glyceraldehyde-3-phosphate dehydrogenase. It is shown that the small shifts (<3.2Hz) in the 31P resonances of 2,3-bisphosphoglycerate which were interpreted to indicate the existence of such complexes (Fossel and Solomon (1977) BBA 464, 82-92) probably result from very small variations in pH (<0.1 unit). Further, no significant resonance shifts are detected in the presence of ouabain in glucose-depleted human red blood cells. An error analysis of the NMR data indicates that previously reported ouabain-induced shifts are within the noise level of the measurement and do not indicate the presence of enzyme complexes in the red cell. © 1979.