Your lab uses the facultative anaerobe E. coli K-12 strain MG1655 as its model organism.  You have been asked to determine which terminal cytochrome oxidases are used in varying environmental conditions.

    1. Which cytochrome terminal oxidase(s) are used during microaerophilic conditions?  Which oxidase(s) are used during high oxygen concentrations?

 

 

    1. Please list which genes encode the two different subunit 1s of the terminal oxidases.

 

 

  1. You wish to further study the regulation of the two cytochrome oxidases operons.  You notice that Fructose-1-phosphate regulates the cytochrome bo oxidase operons.  Explain how it acts and how that affects bo oxidase operon expression.