RESUMO
The "middle molecules", endotoxins of peptide nature appearing in biological fluids in several diseases, cause the disorder of many regulatory processes, suppress the functions of blood cells, affect the transport characteristics of cell membranes. The review covers different aspects of formation, structure and numerous biological effects of "middle molecules", including the molecular mechanism of their biological action.
Assuntos
Peptídeos/sangue , Toxinas Biológicas/sangue , Sequência de Aminoácidos , Transporte Biológico , Membrana Celular/metabolismo , Cromatografia em Gel , Colágeno/metabolismo , Endotoxinas/sangue , Fibrinólise , Humanos , Peso Molecular , Fragmentos de Peptídeos/sangue , Peptídeos/fisiologiaRESUMO
The total semi-empirical conformational analysis of the oxytocin molecule has been carried out. It has been revealed the two main types of stable structures of cyclic moiety backbone and the great lability of the tail. The optimal spacing of cyclic moiety side chains has been found for every backbone structure. The calculation results are in good agreement with the data of physico-chemical investigations. Among the set of stable molecule structures reported in the present study are structures with beta-turn conformation of the cyclic moiety backbone and without closer spacing of the cyclic moiety and the tail, as well as structures with closely spaced N- and C-terminal parts which, however, lack beta-turn in the cyclic moiety.
