title: Conjugation of cytochrome c with hydrogen titanate nanotubes: novel conformational state with implications for apoptosis.
abstract: We show that hydrogen titanate (H(2)Ti(3)O(7)) nanotubes form strongly associated reversible nano-bio-conjugates with the vital respiratory protein, cytochrome c. Resonance Raman spectroscopy along with direct electrochemical studies indicate that in this nano-bio-conjugate, cytochrome c exists in an equilibrium of two conformational states with distinctly different formal redox potentials and coordination geometries of the heme center. The nanotube-conjugated cytochrome c also showed enhanced peroxidase activity similar to the membrane-bound protein that is believed to be an apoptosis initiator. This suggests that such a nanotube-cytochrome c conjugate may be a good candidate for cancer therapy applications.
authors.affiliation: Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India.
authors.forename: Moumita
authors.initials: M
authors.lastname: Ray
authors.forename: Sriparna
authors.initials: S
authors.lastname: Chatterjee
authors.forename: Tanmay
authors.initials: T
authors.lastname: Das
authors.forename: Somnath
authors.initials: S
authors.lastname: Bhattacharyya
authors.forename: Pushan
authors.initials: P
authors.lastname: Ayyub
authors.forename: Shyamalava
authors.initials: S
authors.lastname: Mazumdar
mesh_terms: D000818:Animals; D017209:Apoptosis; D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism; D006736:Horses; D043942:Nanotubes / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010544:Peroxidases / Q000378:metabolism; D011487:Protein Conformation; D014025:Titanium / Q000737:chemistry*
chemical_list: D010087:Oxides; D045304:Cytochromes c; D014025:Titanium; D010544:Peroxidases