this presentation is about identifying and characterizing the genus desulfovibrio

1. Genus
DESULFOVIBRIO

2. General Characteristics
• Desulfovibrio is a genus of Gram-negative, non-spore forming,
mesophillic and curved rod shaped sulfate-reducing bacteria.
• Motile and have polar flagella.
• Commonly found in marine, brackish and freshwater sediments, the
intestines and feces of animals and in high-organic material
environments.
• Anaerobically growing organism. But certain strains have been
identified growing in the presence of oxygen.
• Either chemoorganoheterotropic or chemolithoautotropic.
• Major product of metabolism is H2S.
• Can be observed as pink or peach colour colonies.

3. Taxonomy
Domain: Eubacteria
Phylum: Proteobacteria
Class: Deltaproteobacteria
Order: Desulfovibrionales
Family:Desulfovibrionaceae
Genus: Desulfovibrio
Representative species
D. vulgaris
D. desulfuricans
D.vulgaris
D.desulfuricans

4. Identification & Characterization
• Morphology
Motile, have a spiral to vibrioid
shaped cells with polar flagella.
2.5-10 μm long and 0.5-1.5μm
wide.
• Staining reactions
Gram staining – red colour
colonies (gram negative)

5. • Growth on differential media
For Sulfur Reducing bacteria, the growth
media used is a Bismuth Sulfite Agar
(BSA) medium.
The result obtained is a black bacteria
isolates in the medium indicating that
bacteria can grow well
• Biochemical properties
H2S test is done to see if the bacteria
can reduce sulfur into sulfide during the
process of metabolism.
Test results at TSIA (Triple Sugar Iron
Agar) medium showed positive results
that the surface of media is black which
means that formation of H2S occurred.

6. • Antibiotic Susceptibility
Generally, Desulfovibrio spp. were
highly susceptible to,
sulbactam-ampicillin
meropenem
clindamycin
metronidazole and
chloramphenicol: MIC90s of 6, 4, 0.19,
0.25, and 8 μg/ml, respectively.
In addition, these strains generally
showed high minimum inhibitory
concentrations to piperacillin and
piperacillin-tazobactam.
• Pathogenicity
May be carried asymptomatically in the
human gastrointestinal tract, or may act
as opportunistic pathogens associated
with primary bacteremia and abdominal
infections, such as abscess and
cholecystitis.
Infections are an infrequent cause of
human disease and are often associated
with an intra-abdominal source.

7. • Lipid Analysis
The predominant fatty acid is
3-hydroxytetradecanoic acid.
Dodecanoic, tetradecanoic and
hexadecanoic acid methyl esters can be
found in significant amounts.
• Nucleotide Sequence

8. • Genome Analysis

9. Benefits
• Contribute for the global sulfur
cycle.
• Bioremediation
use in toxic waste cleanup such as
heavy metals and radionuclides.
Disadvantages
• Corrosion of iron pipe lines by
oxidizing iron metal.
Fe(s) Fe2+
(aq)
• Rotten egg smell due to H2S.
• High H2S production can kill local
flora.

10. References
• Asian Journal of Applied Sciences (ISSN: 2321 – 0893) Volume 03 –
Issue 05, October 2015
• Voordow, G. (1995) The genus Desulfovibrio: the centennial. Applied
and environmental microbiology, 61(8), 2813.
• https://www.slideshare.net/mikiask/bacteria-desulfovibrio
• https://www.sciencedirect.com/topics/biochemistry-genetics-and-
molecular-biology/desulfovibrio-vulgaris
• https://www.researchgate.net/publication/47403886_Desulfovibrio_
Bacterial_Species_Are_Increased_in_Ulcerative_Colitis
• https://link.springer.com/article/10.1134/S0026261715040165