[Computer bank of amino-acid sequences of protein hormones. Analysis of evolutionary, conformational and physico-chemical properties of the individual sites of sequences in superfamilies of proinsulin and proglucagon].

The correspondence schemes for the amino acid sequence families from different animal species for two superfamilies of protein-peptide hormones and their precursors, i.e., proinsulin-IGF-prorelaxin and proglucagon-pro (PHM-VIP)-prosomatocrinin, were constructed. These schemes were used for the local intra- and interfamilial comparison of the sequences; the average profiles of hypothetical secondary structure of individual sites of these sequences according to Chow and Fasman were obtained, and the profiles of their physico-chemical properties (e. g., hydrophobicity and volume of side amino acid radicals) were computed. An analysis of the profiles obtained demonstrated that despite the apparent similarity of the tertiary structure of IGF and relaxin, on the one hand, and of insulin, on the other, the latter is devoid of the insulin-like receptor (effector) site, whereas in the case of IGF, this site is modified by additional links of the peptide chain. Based on the reciprocal comparison of prosomatocrinin with proglucagon and pro (PHM-VIP), it was assumed that the C-terminal fragment of prosomatocrinin separated from somatocrinin by a single arginine residue is a second glucagon-like peptide in the precursor molecule, which apparently possesses a biological activity.