Electro-chemical transduction in elastic protein-based polymers: a model for an energy conversion step of oxidative phosphorylation.
A pair of functional moieties, the carboxyl of an aspartic acid (Asp, D) residue and an N-methyl nicotinamide (NMeN) formed on amide linkage to the epsilon-amino group of the lysine (Lys, K) residue, are coupled to perform energy conversion by means of controlling the transition temperature, Tt, of a common hydrophobic folding and assembly domain within the polytricosapeptide, poly[GDGFP GVGVP GVGVP GFGVP GVGVP GVGK(NMeN)P]. The input of electrochemical energy in the form of the reduction of nicotinamide results in a reduction-induced increase in pKa by 2.5 pH units which represents the performance of the chemical work of picking up a proton. The primary structure and the structures of the oxidized and reduced states are verified by two-dimensional nuclear magnetic resonance. Thus electrochemical transduction, the conversion of electrochemical energy into chemical energy, has been demonstrated for the first time in a designed, synthetic protein-based polymer.
Urry
D W
DW
Laboratory of Molecular Biophysics, University of Alabama at Birmingham 35294-0019, USA.
Hayes
L C
LC
Gowda
D C
DC
Peng
S Q
SQ
Jing
N
N
D000595:Amino Acid Sequence; D001224:Aspartic Acid; D004548:Elasticity; D004563:Electrochemistry; D006863:Hydrogen-Ion Concentration; D008239:Lysine; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008969:Molecular Sequence Data; D009536:Niacinamide / Q000737:chemistry; D010084:Oxidation-Reduction; D010085:Oxidative Phosphorylation; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation; D013816:Thermodynamics
D010455:Peptides; D009536:Niacinamide; D001224:Aspartic Acid; D008239:Lysine