Structure-function relationship studies of the cytochrome bd oxidase of Escherichia coli

The cytochrome bd oxidase complex is one of two terminal oxidases which are components of the aerobic respiratory chain of Escherichia coli. This membrane-bound oxidase catalyzes the two-electron oxidation of ubiquinol and the four-electron reduction of oxygen to water. Enzyme turnover generates proton and voltage gradients across the bilayer. The oxidase is a heterodimer containing three heme prosthetic groups, $b\sb{558},$ $b\sb{595},$ and d. To explain the functional properties of the oxidase, a simple model has been proposed in which the heme prosthetic groups define two separate active sites on opposite sides of the membrane at which the oxidation of ubiquinol (heme $b\sb{558})$ and the reduction of oxygen to water (hemes $b\sb{595}$ and d) take place. Two histidines, His19 and His186, both in subunit I have been shown to affect the incorporation of the hemes as well as the activity of the oxidase. His19 is proposed to be an axial ligand to either $b\sb{595}$ or d hemes, whereas His186 is believed to be one of the two axial ligands to heme $b\sb{558}.$

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biology, Molecular

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Ghaim, Joshua Eyassu B.

Contributors dc:contributor

• Gennis, Robert B.

• Biology, Molecular
• Chemistry, Biochemistry
• Biophysics, General

Statement dc:rights

• Copyright 1996 Ghaim, Joshua Eyassu B.

Language dc:language

eng

Identifier

9780591198218
AAI9712281
(UMI)AAI9712281

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/23748