A.T. Mukhametshin, A.R. Kayumov, O.A. Markelov, M.I. Bogachev

We investigated the distribution of amino acids in proteins of two functional groups: membrane-bound and DNA-binding proteins, from gram-positive and gram-negative bacteria. We applied the multifractal detrended fluctuation analysis (MF-DFA) for hydrophobicity, polarity and side chain charge of amino acids. We found that (i) clustering of amino acids with similar properties in membrane-bound proteins is significantly more pronounced in gram-positive bacteria compared to gram-negative ones, especially for hydrophobicity; (ii) multifractal features have been observed only in side chain charge studies. Probably this is an effect of different structure of membrane in gram-positive and gram-negative bacteria. In contrast, while studying DNA-binding proteins no significant differences between gram-positive and gram-negative bacteria has been observed.