Nonionic and zwitterionic forms of glycylglycylarginine as a part of spider silk protein: Spectroscopic and theoretical study

ARI H., Ozpozan T.

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, cilt.152, ss.557-571, 2016 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 152
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1016/j.saa.2014.12.115
  • Dergi Adı: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.557-571
  • Anahtar Kelimeler: Spider silk, Glycylglycylarginine, Zwitterion, Normal Mode Analysis, DFT, POLYCYCLIC AROMATIC-HYDROCARBONS, DENSITY-FUNCTIONAL THEORY, FT-RAMAN SPECTRA, L-ASCORBIC-ACID, HOMO-LUMO GAP, VIBRATIONAL-SPECTRA, MOLECULAR-STRUCTURE, DRAGLINE SILK, INDEX
  • Yozgat Bozok Üniversitesi Adresli: Evet

Özet

Glycylglycylarginine as a part of GGX motif of spider silk spidroin in nonionic (non-GGR) and zwitterionic (zwt-GGR) forms have been examined from theoretical and spectroscopic aspects. The most stable conformational isomers of non-GGR and zwt-GGR were obtained through relaxed scan using the DFT/B3LYP with 6-31G(d) basis set. Nonionic and zwitterionic forms of 3(10)-helix structures of GGR have also been calculated and compared with the most stable conformers obtained as a result of conformer analysis of isolated three peptide structures. This comparison should give an idea about the stability contribution of intermolecular interactions between the 310-helix structured peptide chains. O3LYP and B3PW91 hybrid functionals beside B3LYP have also been used for further calculations of geometry optimization, vibrational analysis, Natural Bond Orbital (NBO) analysis, HOMO-LUMO analysis and hydrogen bonding analysis. Normal Mode Analysis was carried through Potential Energy Distribution (PED) calculations by means of VEDA4 program package. IR and Raman spectra of GGR have also been used to relate the spectroscopic data obtained to electronic and structural features. (C) 2015 Elsevier B.V. All rights reserved.