title: Electrocatalytic monitoring of peptidic proton-wires.
abstract: The transfer of protons or proton donor/acceptor abilities is an important phenomenon in many biomolecular systems. One example is the recently proposed peptidic proton-wires (H-wires), but the ability of these His-containing peptides to transfer protons has only been studied at the theoretical level so far. Here, for the first time the proton transfer ability of peptidic H-wires is examined experimentally in an adsorbed state using an approach based on a label-free electrocatalytic reaction. The experimental findings are complemented by theoretical calculations at the ab initio level in a vacuum and in an implicit solvent. Experimental and theoretical results indicated Ala3(His-Ala2)6 to be a high proton-affinity peptidic H-wire model. The methodology presented here could be used for the further investigation of the proton-exchange chemistry of other biologically or technologically important macromolecules.
authors.affiliation: Institute of Biophysics of the CAS, v.v.i., Kralovopolska 135, 612 65 Brno, Czech Republic.
authors.forename: V
authors.initials: V
authors.lastname: Dorčák
authors.forename: M
authors.initials: M
authors.lastname: Kabeláč
authors.forename: O
authors.initials: O
authors.lastname: Kroutil
authors.forename: K
authors.initials: K
authors.lastname: Bednářová
authors.forename: J
authors.initials: J
authors.lastname: Vacek
mesh_terms: D006639:Histidine; D010455:Peptides / Q000737:chemistry*; D011522:Protons; D012997:Solvents
chemical_list: D010455:Peptides; D011522:Protons; D012997:Solvents; D006639:Histidine