Iron-ATP, a by-product of acid extraction of whole blood or red blood cells

Abstract

Trichloroacetic acid extracts of red cell often produce an iron-ATP complex after ion exchange chromatography of the extract amounting to about 1/3 of the total ATP. In the present work the presence of 14-50% of iron-ATP in such extracts from human and Rhesus monkey blood has been shown.Experiments designed to clarify the possible role and origin of iron-ATP revealed that non-acid treatment of human blood or red cells, as in the freeze-thaw process, followed by separation on a Sephadex column did not produce an iron-ATP fraction. In addition, purified hemoglobin and ATP were combined and incubated at pH 7.4. After Sephadex chromatography, there was no evidence of an iron-ATP fraction. However, similar combinations of incubated hemoglobin and ATP treated with trichloroacetic and separated by ion exchange chromatography did produce an iron-ATP fraction similar to that obtained from acid-extracted blood.It appears that iron-ATP in quantities found in acid-extracted blood is the result of iron release from hemoglobin and the subsequent complexing of such iron with available ATP.