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The oligonucleotide composition of the E. coli genome and its sigma70-specific promoters has been analyzed. The promoter DNA was shown to contain mainly AT-rich hexanucleotides having functionally important physical properties such as the ability to form easily melting sites and induce the bending of the double helix. A comparative analysis of the electrostatic characteristics of hexanucleotides within the whole sequence of the E. coli genome and its promoter regions was made. Hexanucleotides possessing a more electronegative surrounding were found to predominate in the nucleotide sequence of the promoter DNA.

Distribution of electrostatic potential of the complete sequence of E. coli genome was calculated. Comparative analysis of electrostatic patterns for 359 promoter and nonpromoter nucleotide sequences was carried out. It is found that nonpromoter regions are characterized by more homogeneous distribution of electrostatic potential with no common specific elements. Electrostatic patterns of promoter DNAs can be specified due to the presence of some distinctive motifs which may be involved as promoter signal elements in RNA-polymerase-promoter recognition.

A comparative analysis of electrostatic potential distribution for "early" T4 phage promoters was undertaken. The data obtained indicate that there are some particular elements in the patterns of electrostatic potential distribution of promoter DNA specific for promoter groups differing by their functional response to ADP-ribosylation of the alpha-subunit as well as to rpoB403- or rpoB409 mutationals of the beta-subunit of RNA-polymerase.