Characterization of Enrichment Cultures of Nitrate-Reducing
Bacteria from Deep-Sea Hydrothermal Vents
Caroline Toney* and Costantino Vetriani
Caroline Toney
crt8347@uncw.edu
(828) 429-9476
Introduction
Conclusions
Deep-sea vents are one of the last
frontiers of the unexplored world. These
unique environments spew forth superheated fluid that is laden with metals.
The base of life which allow other
organisms to live in this ecosystem are
microorganisms which undergo
chemosynthesis as a means of primary
production.
•The molecular characterization of the
organisms cultured in the samples taken
from the dives reveals that there may be
new species among them.
•The sequences of the 16S rRNA gene from
the organisms grown show that further
isolation is needed for some samples in
order to have a pure culture from which
further investigation of the species can be
done.
• Future work would include
characterization of isolated organisms.
Morphological observation and studies of
optimal growth in temperature, salinity
and pH will be executed. Metabolism will
be studied through growth under different
conditions (i.e. electron donors and
acceptors, pressure, etc.), in organic
substrates, and resistance to antibiotics
will also be tested.
Alvinella pompejana. (noc.soton.ac.uk)
Crab Spa
(whoi.edu)
Samples were taken during Nautile Dive (ND) #:
ND 1726 Alvinella pompejana tubes
ND 1727 Alvinella pompejana encrusted sulfides
ND 1729 Fluid from Crab Spa; Bottom Seawater
Media
Carbon Source Electron
Donor
Electron
Acceptor
Temp (°C)
HB1
CO2
H2
NO3
50 & 75
Sulfurovum
CO2
N2, thiosulfate NO3
35
Sulfurimonas CO2
H2, thiosulfate NO3
35, 50
ASW
N2
30
Organic
NO3
Table 1. Characteristics of anaerobic media used.
Figure 1. Illustration of deepsea hydrothermal vent flow.
(Brock et al., 2006).
Site
Media
Temp (°C)
Identity (%)
Description
Alvinella
Tubes
HB1
50
99,97
Sulfurimonas
35, 50
86
HB1
50
97, 96
97
100
Caminibacter
mediatlanticus; Nautilia
profundicula, abyssi
Sulfurospirillum
carboxydovorans
Caminibacter
mediatlanticus
Desulfobacterium
pacificum
Thioprofundum
lithotrophica; Rhodobacter
capsulatus; Marinobacter
hydrocarbonoclasticus
Shewanella haliotis
Klebsiella pneumoniae
99
Shewanella haliotis
Figure 2. Sampling sites of deepsea hydrothermal vents on the East
Pacific Rise
Objectives
• To grow cultures from samples taken at
vent sites at 9°N and 13°N.
•To isolate anaerobic, nitrate-reducing
bacteria using different techniques
and media.
•To compare the 16S rRNA gene sequences
of these organisms to the database
using BLAST (Basic Local Alignment
Search Tool) to assess their
relatedness to other species.
Alvinella
sulfide
HB1
Crab Spa
Sulfurovum
75
35
Sulfurimonas
35, 50
Anaerobic ASW 30
Bottom
Anaerobic ASW 30
Seawater (B)
98
93;96;93
Table 2. Results of sequencing and BLAST.
Acknowledgements
We want to thank the crew of the R/V L’Atlante and the
crew and pilots of the DSV/Nautile for sample collection
We would like to offer our thanks to the members of the
Deep Sea Microbiology Lab at Rutgers University their
expertise, as well.
This work was supported by an NSF grant.