Aerobic Respiration - Exercise #3

Your lab uses the facultative anaerobe E. coli K-12 strain MG1655 as its model organism.  You have been asked to study the various dehydrogenases used in aerobic environmental conditions.

  1. NADH dehydrogenase II  is used to oxidize NADH during aerobic respiration.  Name two pathways that generate NADH. 


  3. Does this dehydrogenase pump protons to the periplasmic space?  If so, how many protons?  If not, name the purposes it serves.


  5. The electrons from the oxidation of NADH (by NADH dehydrogenase) are ultimately used by a reductase complex to reduce O2 to H2O.  During aerobic respiration, would E. coli use Nitrate reductase, Cytochrome bo oxidase or DMSO reductase?  Explain briefly.