ABSTRACT
Mosquitoes are a problem in temperate and tropical zones of the world. Two media used to culture mosquito cells are H. Eagle's MEM and A. Leibovitz's L-15. Mosquito cell lines derived from different genera were used. Malarial parasites depend on their host for a supply of exogenous purines, primarily hypoxanthine, as they cannot synthesize them de novo. Aminopterin blocks the de novo synthesis of purines and pyrimidines by inhibiting the enzyme dihydrofolate reductase. Leibovitz's L-15 medium was used for the isolation and initial maintenance of cell lines. Various combinations of purines and pyrimidines were tested with respect to their ability to replace tryptose phosphate broth and to salvage cells made auxotrophic by addition of aminopterin. In the mosquito cell lines, both de novo and salvage pathways of nucleotide metabolism were functional. Arthropod cells in culture either synthesize purine and pyrimidine nucleotides de novo or salvage bases from the medium.
