Metabolism of Babesia parasites in vitro. amino acid production by Babesia rodhaini compared to Plasmodium berghei.

The in vitro amino acid production by Babesia rodhaini, Plasmodium berghei and uninfected rat erythrocytes was determined following 4 and 18 h of incubation in Krebs Ringer medium. Both parasites produced excess free amino acid. B. rodhaini produced up to 150 times and P. berghei up to 1,100 times as much free amino acid as parasite-free rat erythrocytes. The composition of excess amino acids produced by both parasites had a statistically significant concordance with the amino acid composition of rat haemoglobin, suggesting that haemoglobin was probably the main source of the amino acids produced by the parasites.