Article
Proton transport by a bacteriorhodopsin mutant, aspartic acid-85-->asparagine, initiated in the unprotonated Schiff base state.
Proceedings of the National Academy of Sciences of the United States of America - 5 Dec 1995
Dickopf S, Alexiev U, Krebs M P, Otto H, Mollaaghababa R, Khorana H G, Heyn M P
Abstract excerpt
At alkaline pH the bacteriorhodopsin mutant D85N, with aspartic acid-85 replaced by asparagine, is in a yellow form (lambda max approximately 405 nm) with a deprotonated Schiff base. This state resembles the M intermediate of the wild-type photocycle. We used time-resolved methods to show that this yellow form of D85N, which has an initially unprotonated Schiff base and which lacks the proton acceptor Asp-85,...
Topics
- Asparagine
- Aspartic Acid
- Bacteriorhodopsins
- Biological Transport
- Light
- Membrane Potentials
- Mutation
- Protons
- Schiff Bases
- Spectrophotometry
- Titrimetry