A new approach to evaluating the sign of chirality (helicity and superhelixity) in the structural hierarchy of proteins is proposed. To determine the sign and magnitude of the chirality of the secondary structure of proteins, an analysis of the relative location of α-carbons was carried out. The angle between the vector of the helix direction and the vector of the sum of vector products allows to unambiguously identify the direction of rotation of the helix in the molecule. This method allows the construction of chiral maps, where the areas corresponding to the narrow range of possible angles for the two types of secondary helix structure are clearly marked.
proteins, chirality, enantiomers, alpha-carbon, right alpha-helix, left polyproline helix, vector product, direction vector, chirality map
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