THE STRUCTURE OF YEAST NUCLEIC ACID

Abstract

The tetranucleotide theory of the structure of yeast nucleic acid was first enunciated by the writer1 and was subsequently conclusively demonstrated by the experimental evidence furnished by Levene and Jacobs,2 'and by Levene and La Forge.3The facts on which the theory was based were: first, the isolation of four nucleosides; second, the isolation of simple pyrimidine nucleotides.These were obtained on partial hydrolysis of yeast nucleic acid.The third fact, important for the development of the t.heory, was the elucidation of the order of linkage of the componentjs of one simple mononucleotide.4The experimental data obtained until that phase of work permitted no rational formulation of the mode of linkage between individual mononucleotides.Our original graphic representation of the entire molecule of yeast nucleic acid had only an arbitrary schematic sense.In a publication on thymus nucleic acid, Levene and Jacobs made that point clear.Owing to pressure of other work, our own investigations into the problem of the linkage of the mononucleotides was making slow progress, when Thannhauser with his collaborators,5 and Jones with his collaborators6 entered the field of nucleic acid study.