Some aspects of nitrogen metabolism in strain L cell cultures

Abstract

Dietary proteins are expended in cell culture; about ten times as much protein is expended as is utilized in the biosynthesis of new protein. The cells utilize only a small fraction of the dietary amino acids in the production of new protein. The cells (Strain L, clone 929) make some glutamine biosynthetically, but not enough to meet their requirements. The glutamine is incorporated into new cell protein, and glutamine nitrogen into nucleic acid. The free nucleotides, the RNA, and the DNA appear to be synthesized independently of each other. The adenine nucleotide nitrogen, as well as the guanine nucleotide nitrogen of both RNA and DNA, respectively, are synthesized from the amide glutamine nitrogen to supply the three and nine nitrogen atoms. It appears that an additional glutamic amide nitrogen atom is incorporated into the guanine moiety, as has been demonstrated in other systems [2].