Dietary nucleotide requirements of the mosquito, Culex pipiens

Dietary nucleic acid, or certain constituents thereof, is essential for full development of the mosquito Culex pipiens. Yeast RNA, whole or hydrolysed, is fully effective. Sperm DNA is totally ineffective on its own, but becomes fully effective when supplemented with uridylic acid. RNA can be replaced with only partial success by a mixture of its component nucleotides (adenylic, guanylic, cytidylic, and uridylic acids), but with the addition of thymidylic acid (characteristic of DNA but present in RNA only as a minor component of transfer RNA), the resulting five-nucleotide mixture is a fully adequate replacement for yeast RNA. Single and multiple deletions from this five-nucleotide mixture showed a minimal requirement for three nucleotides: adenylic acid (a purine ribonucleotide) and thymidylic acid (a pyrimidine deoxyribonucleotide) were both specifically required; as the third nucleotide, either cytidylic or uridylic acid (both pyrimidine ribonucleotides) was equally satisfactory. Mixtures of the five nucleosides or five deoxynucleotides corresponding in base composition to the effective five-nucleotide mixture were only partially effective substitutes.