Energy Sources for H^m Synthesis 



87 



nearly complete haemolysis, the incorporation of ^^N glycine 

 was markedly inhibited (Table I). 



Table I 



Effect of Hemolysis on Synthesis of Hjem by Fowl Erythrocytes 



It was clear therefore that intact red cells would have to 

 be used and that any test in which haemolysis occurred would 

 have to be interpreted with great caution. 



The most obvious possible source of energy for haem syn- 

 thesis within the erythrocytes is the metabolism of glucose, 

 but when extra glucose was added to the suspending medium, 

 no increase in ^^N incorporation occurred. This would be 

 easily explicable were the quantity of carbohydrate available 

 to the cell already sufficient to supply all energy needs. Cells 

 were therefore washed and resuspended in dialysed fowl 

 plasma. Unfortunately some haemolysis could not be pre- 

 vented during the subsequent incubation but it appeared 

 that the addition of glucose was without any stimulating 

 effect. A similar experiment was carried out with acetate and 

 a negative result obtained in this case also (Table II). 



Table II 



Addition of Glucose or Acetate to Washed Fowl Erythrocytes in 



Dialysed Plasma 



Attempts were then made to interfere with the course of 

 carbohydrate metabolism by the use of the well known 



