revealing the identity of oil-degrading microorganisms at deepwater horizon - tony gutierrez
DESCRIPTION
Centre for Marine Biodiversity and Biotechnology Open Day 2012. Presentation by Tony Gutierrez.TRANSCRIPT
Revealing the Identity of
Oil-Degrading Microorganisms
at Deepwater Horizon….and a little more
Overview
1. Deepwater Horizon oil spill in the GoM. Where did most of the oil go? Who’s responsible?
2. On the formation of ‘Oily Snot’ during DWH spill.
3. FISH’n for oil-degrading bacteria.
4. Knowns and Unknowns about the DWH spill.
Deepwater Horizon Mucondo well site
B Incubation of sample on labeled 13C PAHs
Whole DNAextract
DNAAssimilation of labelby active microbes
“ light ”
“ heavy ”
- PCR of 16S rRNA- Cloning- Sequencing
A
OH
COO-
O
Uniformly-labeled 13C Naphthalene
trans-2-hydroxy-benzylidenepyruvate
Degradation Further metabolism
Incorporation of the 13C atoms into cellular biomass
(e.g. DNA)
“ Heavy ” DNA
Identifying Who Degraded the Oil by Stable-Isotope Probing (SIP)
Gutierrez, T. (2011) Rev Environ Sci Bio/Technol.
10 mmP
erc
en
t c
ha
ng
e
-100
0
100
200
300
400
500
7
0 0
2
PE5
B6 B11
B1
What about that ‘Oily Snot’
Polymer concentration (mg/mL)
0.0 0.2 0.4 0.6 0.8 1.0
Hyd
roca
rbo
n c
on
cen
trat
ion
(m
g/L
)
0
10
20
30
40
50 A
FISH’n for Oil-Degrading Bacteria
G-T-G-C-C-G-C-T-A-T-C-G-A-A-T-T-C-G
( Fluorescence In Situ Hybridization )
Alpha-proteobacteria associated with Pseudonitzschia diatom
Probes used: EUB-Cy5 / Alpha-Cy3
Marinobacter (green) + DAPI (blue)Marinobacter (green/yellow)
vs. others (red)
Beginning of enrichment 4 days later
Gulf of Mexico Plume Water Enriched with Oil
Overview about the DWH Oil Spill: a microbial perspective
Knowns:- Mobility / Fate of the oil- Bacteria largely responsible in ultimate removal of the oil- The types of bacteria that dominated and were likely responsible for degrading much of the oil- We know that all of the oil is now gone from the water column; but residual oil remains in the sediment.
Not-So-Well Knowns:- Detail on the microbial response and succession of this response over the course of the spill- What diversity of bacteria contributed, and by how much? What was their function?
Acknowledgements
Colleagues/Collaborators• Prof. Mike Aitken (UNC, Chapel Hill)• Prof. Andreas Teske (UNC, Chapel Hill)• Dr. Kirk Semple (Univ. Lancaster)• Dr. Alexander Loy (Univ. Vienna, Austria)• Luke McKay (UNC, Chapel Hill)• Tingting Yang (UNC, Chapel Hill)• Sara Mishamandani (UNC, Chapel Hill)
Funders• European Commission (Marie Curie Programme)• NSF Rapid Response Grant• UNC fellowship program