title: [Left helix of polyproline II type and genesis of beta-structures in spidroins 1 and 2 and their recombinant analogs].
abstract: The distribution of secondary structures along the polypeptide chains of spider proteins spidroins 1 and 2 and their recombinant analogs has been studied by statistical methods. It was found that these proteins in the monomolecular form contain only trace amounts of beta-structures. At the same time, the regions of the sequence including Ala and Gly are predicted as helical-containing (with alpha-helices and left-helices of polyproline II type). An analysis of literature data and our data obtained in this study shows that the main conformation of the polypeptide chain solutions of spidroins 1 and 2 and their recombinant analogs in water solutions is the left-helix of polyproline II type with some contaminations of alpha-helices and a very small share of beta-structures. The transition to the state with extended conformations, which are peculiar to mature filaments of spider webs, requires the dehydration of the polypeptide chain backbone. Thus, the genesis of beta-structure in spider web proteins is determined by the conditions of conformation transitions between the main regular conformations of the polypeptide chain backbone.
authors: N G
authors: NG
authors: Esipova
authors: L E
authors: LE
authors: Ragulina
authors: L I
authors: LI
authors: Davydova
authors: V M
authors: VM
authors: Lobachev
authors: V Iu
authors: VIu
authors: Makeev
authors: V G
authors: VG
authors: Bogush
authors: V G
authors: VG
authors: Tumanian
authors: V G
authors: VG
authors: Debabov
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005349:Fibroins / Q000737:chemistry*; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry; D013112:Spiders
chemical_list: D010455:Peptides; D011994:Recombinant Proteins; C086087:spidroin 1; C076815:spidroin 2; C011083:polyproline; D005349:Fibroins