[Cluster analysis of mirror type internal symmetry in amino acid sequences of heterotrimeric G-protein alpha-subunit superfamily].

For the identification of mirror type internal symmetry centers in amino acid sequences (AASs) the new method, named by the method of internal symmetry scanning, was developed. The method, contrary to earlier ones, can be used for analysis of large clusters of primary structures of related proteins. The internal symmetry centres, containing both one and two amino acid residues, can be identified rapidly and effectively by the method. Additionally, the new method allow to estimate quantitatively the homology of AASs, which are antiparallel to relation of the centres. The different modifications of the method can be used for revealing of both high conservative and unequal symmetrical structures in AASs of proteins. Usually the structures coincide with functionally important regions of protein molecules. The method was used for investigation of primary structures of members of heterotrimeric G-protein a a-subunit superfamily. The positive correlation between conservativity of primary structure and distribution of mirror type internal symmetry centres was shown.