2. OVERVIEW
o Sergei Winogradsky
o Pond mud
diverse microbial communities
o Clear-glass cylinder
Mud samples
water
excess substrates (optimal growth)
o Sun light (synthetic or otherwise)
o O2 gradient – H2S gradient
o Multiple layers
Sergei Winogradsky
3. o Diverse
microbial
communities
o lots of stuff in
soil
o Many samples
o Symbiosis
between
bacteria
o Anaerobe rich
MUD SAMPLES
4. THE COLUMN
700 mls Mud
1 scoop
Cellulose
1 scoop
Calcium sulfate
300 ml Tap
Water
Foil or parafilm
5. ADDITIONAL SUBSTRATES
C E L L U L O S E
• Carbon source
• Anaerobic
bacteria
• Examples:
• Clostridium
• Bacillus
C A L C I U M
S U L FAT E
• Sulfur source
• Sulfate reducing
bacterium
• Examples:
• Desulfovibrio (sulfate
reducer)
• Chlorobium (sulfur
oxidizer)
• Chromatium
• Green Sulfur bacteria
11. PINK LAYER
N O N - S U L F U R
B A C T E R I A
Aero-tolerant
Phototrophic
Lower H2S tolerance
Various carotenoid
pigments –
bacteriochlorphyll A or B
Examples:
Rhodospirillum
Thiobacillus
RHODOSPIRILL
UM
14. PURPLE LAYER
S U L F U R B A C T E R I A
Anoxygenic
Phototrophic
Higher H2S tolerance
Various carotenoid
pigments
Examples:
Chromatium
Thiocapsa
CHROMATIU
M
16. BLACK LAYER
M O R E S U L F U R
B A C T E R I A
Anaerobic
Cellulose Fermentation
Carbon Source
Sulfate-reducing
H2S combines with metals in
mud to form metal sulfides
(Black pigment)
Examples:
Clostridium
Desulfovibrio
17. GREEN LAYER
G R E E N S U L F U R B A C T E R I A
Anoxygenic photosynthetic
bacteria
H2S – electron source
- Sulfur production
Green – chlorophyll
Examples:
Chlorobium
22. CONCLUSION
• A lot of the soil was dry/sandy
• Better light source
• Pond water instead of tap water
• More cellulose powder and calcium sulfate
• Other options??
• Newspaper shavings (cellulose)
• Blackened marshmallows/ egg shells (calcium carbonate)
• Egg yolk (Sulfur source)
• Soil not packed densely enough – air pockets
• More time?
