Nanosecond ligand migration and functional protein relaxation in ba(3) oxidoreductase: Structures of the B-0, B-1 and B-2 intermediate states

作者：Nicolaides Antonis; Soulimane Tewfik; Varotsis Constantinos

来源：Biochimica et Biophysica Acta-Bioenergetics, 2016, 1857(9): 1534-1540.

DOI：10.1016/j.bbabio.2016.05.002

• Cytochrome c oxidase
• Time-resolved step-scan FTIR
• Dynamics

Nanosecond time-resolved step-scan FTIR spectroscopy (nTRS (2) -FTIR) has been applied to literally probe the active site of the carbon monoxide (CO) -boundthermophilic ba(3) heme-copper oxidoreductase as it executes its function. The nTRS (2) - snapshots of the photolysed heme a(3) Fe-CO/Cu-B species captured a "transition state" whose side chains prevent the photolysed CO to enter the docking cavity. There are three sets of ba3 photoproduct bands of docked CO with different orientation exhibiting different kinetics. The trajectories of the "docked" CO at 2122, 2129 and 2137 cm(-1) is referred to in the literature as B-2, B-1 and B-0 intermediate states, respectively. The present data provided direct evidence for the role of water in controlling ligand orientation in an intracavity protein environment.

• 出版日期2016-9