The breakdown of 2,3-bis(phospho)-D-glycerate by Fe(III)-haemoglobin

Fe(III)-haemoglobin is shown to catalyse the hydrolysis of 2,3-bis(phospho)-D-glycerate to Pi and 3-phosphoglycerate, although the rate is slow, even when the protein is present at concentrations in the millimolar range. The rate of hydrolysis is proportional to the subtrate concentration up to at least 10 mM, so if the process is enzymic, the Km must be high.