The distribution of nucleotides in deoxyribonucleic acid

Abstract

A combination of paper chromatography and paper electrophoresis has been used to separate the pyrimidine oligonucleotides obtained through the action of acid diphenylamine solution and phosphomonoesterase on deoxyribonucleic acid. Thirty-four components, consisting of oligonucleotides containing up to nine pyrimidine residues, have been separated and identified with respect to pyrimidine composition and chain length. Many of these, however, consist of mixtures of isomeric sequences in unknown proportions. The amounts of these components in digests of calf-thymus deoxyribonucleic acid and herring-testis deoxyribonucleic acid have been measured. Many of the sequences were present in amounts significantly different from those expected on the basis of a random distribution of nucleotides in deoxyribonucleic acid, but, in accordance with earlier conclusions, no general trend common to both nucleic acids was seen. Sequences of four consecutive deoxycytidylic acid residues were found in digests of deoxyribonucleic acid from calf thymus, herring testis. Alcaligenes faecalis and Pseudomonas aeruginosa. Sequences of five consecutive deoxycytidylic acid residues were not detected in any of these four preparations and therefore may be absent.