Transcript Bioluminescent Bacteria

Marine
Bioluminescence
Holly Sewell
23 July 2010
Marine Bioluminescence
Experiment
Organisms and Environments
Where is it found?
Function
Proposed explanations
Genes
Reaction
www.ou.edu
www.ou.edu
Experiment:
Can we isolate bioluminescent colonies?
SWC
SWC
Bacterial Bioluminescence
Where is it found?
Estimated 1-6x103 free-living bioluminescent bacteria per liter of water
Photobacterium
www.bioart.co.uk
Vibrio
www.alchemipedia.com
Photorhabdus
www.asm.com
Some colonize light organs, producing light for animal
for signaling
avoiding predators
attracting prey
Parasites in crustacea
Proposed explanation for
bacterial bioluminescence
Anaerobic bacteria may have developed bioluminescence to use up toxic oxygen
(Tett & Kelley, 1973)
Catalyze the transfer of electrons to oxygen
(Nealson & Hastings, 1979)
High population density quorum sensing:
attract animals to feed  dispersal of population
(Microbiology, Brock)
Stimulation of DNA repair
(Czyz et. al, 2000)
www.pubs.acs.org
Bioluminescence Genes
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lux I
lux R
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Activation of
luminescence
genes
Bioluminescence reaction:
How it works
Luciferin + O2
Luciferase
Oxyluciferin + Light
Light
NAD(P)H + H+
Oxidoreductase
RCOOH
Luciferase
NAD(P)+
FMNH2 + O2 + RCHO
Reductase
RCHO
O2
Luciferase
NAD(P)H + H+
ATP
Fatty Acid
NAD(P)+
AMP + PPi
FMN + RCOOH + H2O + Light
Questions?
An Example of Bacterial Bioluminescence
Light Organ colonization in Euprymna scolopes
Colonized by Vibrio fischeri
both light and presence important for development of squid
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