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R E Isaacks

Publications and source records attributed to R E Isaacks.

11 recordsLinked to original sources
PubMed1979

Oxygen binding of fetal and adult bovine hemoglobin in the presence of organic phosphates and uric acid riboside.

The P50 values of "stripped" fetal and adult bovine hemoglobin were 18.4 and 28.9 respectively. Neither the oxygen-hemoglobin dissociation curve nor the Hill coefficient, n, of fetal or adult bovine hemoglobin was affected by uric acid riboside (UAR), 2,3-diphosphoglyceric acid (2,3-DPG), adenosine triphosphate (ATP), or inositol pentaphosphate (IPP). Combinations of UAR and ATP with adult bovine hemoglobin or 2,3-DPG and ATP with fetal hemoglobin also had no effect. It was concluded that neither adult nor fetal bovine red cells contained an identifiable compound which affects the binding of oxygen to hemoglobin.

Adenosine Triphosphate↗
PubMed1977

Studies on avian erythrocyte metabolism. VII. Effect of inositol pentaphosphate and other organic phosphates on oxygen affinity of the embryonic and adult-type hemoglobins of the turkey embryo.

The effects of 2, 3-diphosphoglyceric acid (2, 3-DPG), adenosine triphosphate (ATP), inositol tetraphosphate (ITP), inositol pentaphosphate (IPP), and inositol hexaphosphate (IHP) on oxygen affinity of whole stripped hemoglobin (WSH), hemoglobin H (Hb-H; hatching hemoglobin), hemoglobin A (Hb-A), and hemoglobin D (Hb-D) isolated from erythrocytes (RBC) of the 25-day turkey embryo have been studied. The order of the decrease in oxygen affinity induced by these organic phosphates, at molar ratios of phosphate compound to hemoglobin (tetramer) between 2 and 4, is 2, 3-DPG less than ATP less than ITP less than IPP less than IHP. 2, 3-DPG shows a slightly greater effect on reducing oxygen affinity of Hb-H than on either adult-type hemoglobin. The effect of IPP upon lowering the oxygen affinity of either WSH, Hb-H, Hb-A, or Hb-D is approximately 20 percent less than IHP. The effects of the various organic phosphates upon the Hill constant, n, of these purified hemoglobins is variable but appears to reach a maximum when the molar ratio of organic phosphate to hemoglobin (tetramer) is 2 or greater. None of the physiologically occurring organic phosphates has a significant preferential interaction with any specific hemoglobin. These experiments strengthen and support our earlier conclusion, that the changes in whole blood oxygen affinity which occur during avian development result from the changes in composition of the intraerythrocytic organic phosphates.

Adenosine Diphosphate↗