The metabolism of Plasmodium berghei, the malaria parasite of rodents. I. The preparation of the erythrocytic form of P. berghei separated from the host cell

Abstract

1. 1. A method is described for the separation of Plasmodium berghei from the red cells of mice or rats. Most parasites obtained in this way were still attached to the stroma of red cells indicating a firm binding between parasite and host cell membrane. 2. 2. These separated parasites had a definite although low degree of infectivity towards fresh host animals. 3. 3. Washed parasites did not contain detectable endogenous substrates and when suspended in a buffered isotonic salt solution the catabolism of added glucose was greatly enhanced when the K +: Na + ratio corresponded to that found in the red cell than when this ratio was that of serum. 4. 4. In an extract of normal reticulocytes, the extent of glucose catabolism of free parasites was comparable with that which could be attributed to the parasite in the intact or lysed infected cell. In contrast oxygen consumption was much reduced. This latter comparison may not however be valid since it is doubtful whether oxygen consumption is directly related to glucose catabolism in infected and normal reticulocytes.