Volume 7, Number 3, p.p. 107–116
Investigation of collagen-DNA films
David V. Svintradze,1,* George M. Mrevlishvili,1 Nunu Metreveli,1,2 Ketevan Jariashvili,1 Luisa Namicheishvili,1 Joana Skopinska3 and Alina Sionkowska3
1 Faculty of Exact and Natural Sciences, Institute of Physics, Tbilisi State University, Chavchavadze Ave 3, Tbilisi 0128, Georgia
2Faculty of Physics and Mathematics, Ilia Chavchavadze State University, Chavchavadze Ave 32, Tbilisi 0157, Georgia
3Faculty of General Chemistry, N. Copernicus University, Gagarin 7, 87-100 Torun, Poland
The normal self-association processes of collagen include fibril formation, while pathological aggregation of collagen is implicated in some collagen diseases. This work concerns the nature of collagen aggregation and the molecular and environmental determinants of the self-association processes in the presence of DNA. Self-association of the collagen-DNA functional complex offers an opportunity to characterize a unique system, which may be related to the physiological self-association of collagen molecules via water bridges. To characterize the collagen-DNA interaction we have conducted FTIR-ATR, NMR and AFM experiments on separate collagen films, DNA films and on peptide-DNA aqueous solutions. We demonstrate that collagen-DNA ordered aggregates spontaneously form self-assembling complex systems in aqueous solution. Such self-association of the complex may be induced by electrostatic interactions between neutral collagen cylinders, having a strong dipole moment and negatively charged DNA cylinders. The final complex may be formed by the hydrogen bonds between specified donor groups of collagen and the phosphate acceptor groups of DNA. According to the FTIR measurements during collagen-DNA complex formation, the collagen triple helix should not change its global conformation.
Keywords: AFM, collagen, complex, DNA, FTIR-ATR, NMR