title: Periodicity in DNA primary structure is defined by secondary structure of the coded protein.
abstract: A 10.5-base periodicity found earlier is inherent in both eu- and prokaryotic coding nucleotide sequences. In the case of noncoding eukaryotic sequences no periodicity is found, so the 10.5-base oscillation seemingly does not correlate with the nucleosomal organization of DNA. It is shown that the DNA fragments, coding the alpha-helical protein segments, manifest the pronounced 10.5-base periodicity, while those regions of DNA which code the beta-structure have a 6-base oscillation. The repeating pattern of nucleotide sequences can be used for comparison of the DNA segments with low degree of homology.
mesh_terms: D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000235:genetics*; D005815:Genetic Code; D008970:Molecular Weight; D009690:Nucleic Acid Conformation; D009707:Nucleosomes / Q000378:metabolism; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D009707:Nucleosomes; D011506:Proteins; D004247:DNA