Metabolism of Alkanes and
Degradation of Chlorinated Ethenes
by the Bacterium
Pseudomonas butanovora
Kate Bateman
Mentors: Dr. Daniel Arp
David Doughty
Department of Botany and Plant Pathology
BIOREMEDIATION:
P. butanovora is capable of removing harmful
chemicals (chlorinated ethenes) from the
environment
•Uses: Industrial cleaners and creation of plastics
•Extensive groundwater pollution
•Drinking water pollutants:
Toxic to the liver, kidneys,
and nervous system
Linked to cancer and birth
defects
•EPA goal for complete
removal not yet reached
Trichloroethylene (TCE) Plume
BMO enzyme: Butane monooxygenase
-Oxidizes alkanes (ethane, propane, butane)
-Cooxidizes variety of chlorinated ethenes
•Pump organisms and
their food (alkane) into
the contaminated
ground water
Goal:
Understand relationship
between metabolism of
their food source and
cometabolism of toxic
compound
Example of a bioreactor
Objective:
Determine the relative affinity of the BMO
enzyme’s active site for a range of alkanes
Butane
Propane
Nothing
competes 1
with propane
Ethane
competes 2
with propane
Butane
competes 3
with propane
 (Increasing affinity for BMO active site)
 (Decreasing alkane concentration)
Goal: Examine relationship between
metabolism of the alkane and
cometabolism of the chlorinated ethene
while the culture is growing
72%
87%
94% of TCE
degraded
76% of TCE
degraded
•BMO’s active site has a higher
affinity for butane than ethane
•Butane-grown cultures degrade more
TCE and at a faster rate than ethane or
propane-grown cultures
Howard Hughes Medical Institute
Dr. Daniel Arp
Dave Doughty