Study of the periodic arrangement of amino acid residues in fiber proteins of bacteriophage T4

Abstract

The amino acid sequences of some fiber proteins possibly have a periodic structure. This periodicity can be analyzed using the Fourier transform of the mathematical image of the symbol sequence of amino acid residues in proteins. One of several possible methods of Fourier transform has been chosen as optimal for the given study. This optimal Fourier transform has been used to analyze the periodic structures in several fiber proteins of bacteriophage T4. Amino acids from some groups form sequences of alternating elements with a relatively small period (T=15); those from other groups form sequences with other small periods (T=10 and T=8). Relatively large periods of amino acid arrangement, with the entire amino acid sequence of the protein being divided between them into four or six equal parts, is a new finding. The data on protein structural periodicity make it possible to align the amino acid sequences according to the periodic structures of both type. The results obtained agree with the results of previous crystallographic and electron microscopic studies.