1. Environmental Microbiology

2. Applied & Environmental Microbiology
applied microbiology is the interaction of the microbial world and the rest of the world
genetic variances
microbial effect on soil, water, our food
microorganisms are present in most every aspect of our lives
microorganisms are critical to our survival on Earth
to be a successful ecosystem on Earth, you’d best be nice to the microorganisms!

3. Microbial Ecology: relationship of microorganisms with each other and their environment
ecosystem: interaction of living and non-living components
oceans, deserts, marshes, forests, tundra, lakes
microorganisms play a key role in ecosystem structure

4. Microbial Ecology: relationship of microorganisms with each other and their environment
microenvironment: immediately surrounds a microorganism
relevant to survival and growth of the microorganism

5. Nutrient Acquisition within an Ecosystem
3 main levels exist in every ecosystem in regards to nutrient acquisition
producer
consumer
decomposer
1. primary producers:
convert CO2 to
organic material

6. Nutrient Acquisition within an Ecosystem
2. consumers
heterotrophs
utilize organic material created by producers

7. Nutrient Acquisition within Ecosystem
3. decomposers
heterotrophs
digest leftovers of primary producers and consumers
detritus ( fresh or partially decomposed organic matter)
bacteria and fungi are key players in the process of decomposition

8. Low Nutrient Environments: common in nature
bacteria do best in biofilms if nutrition availability is low
biofilms are a polysaccharide encased community of microorganisms
microorganisms extract nutrients that are absorbed by water from air or nutrients that are adsorbed onto the biofilm

9. Microbial competition and antagonism
most environments are suitable to many kinds of microorganisms
only one or a few can actually occupy the environment at a given time

10. Competition and Antagonism: among microorganisms
fierce competition for nutrients and water
the faster a microbe reproduces the larger the population
the larger population competes better
critical, especially if the microorganisms competing utilize similar nutrients
antagonism
bacteriocins: protein produced by bacteria that destroys similar strains
“WINNER TAKES ALL AND IS KING/QUEEN OF THE MICROBIAL ECOSYSTEM”

11. Example of Competition
stability of microbial community in human intestine is attributed to competition and antagonism amongst its members
compete nicely for nutrients
produce toxins to limit growth of new microbes

12. Environmental Change affect microbial population
environmental fluctuations are common and resident microorganisms may respond by
producing enzymes to help adapt to changing environment
additional or different enzymes may be necessary for survival
mutation
domination by other species (can’t compete any more)

13. Microbial Mat: thick, dense, organized biofilm
generally found attached to a solid substrate or at air-water interfaces
Microbial mat attached to rocks
Microbial mat in stream bed

14. The Study of Microbial Ecology
somewhat difficult to accomplish
less than 1% of environmental microorganisms can be successfully cultured in the lab

15. Microbial Habitat aquatic marine:
deep waters are usually stable and consistent
shoreline habitat varies due to nutrient rich run-off

16. Microbial Habitat freshwater: lakes
stratification allows for the mixing of the water seasonally.
Increases the presence of O2 in the deeper H2O
algae
paramecium

17. Microbial Habitat moving water rivers
generally aerobic due to turbulence facilitating O2 circulation
river ostracod

18. Microbial Habitat terrestrial
microorganisms are critical to soil habitat
composition of microbes is dependent on soil conditions
wet soil: anaerobic conditions due to water filling the pore space in the soil, soil dries and microbes go produce endospores for survival
Endospores

19. Mutualism with Eukaryotes
mychorrhizae: fungus
assist plants in the uptake of phosphorous
mychorrizae gain nutrient from plant

20. Mutualism
nitrogen fixers: fix nitrogen and make it available for the use by their partner plant
most common is Rhizobium, a microorganism found in many root nodules
Rhizobium in root nodules

21. Nitrogen Cycle

22. Carbon cycle

24. Mutualism: microorganisms and the world
microorganisms and herbivores
animal with a rumens (cow) or cecums (horse) need microorganisms to digest the plant food they ingest
Bacillus in a cow rumen

25. Microorganisms in Sewage Treatment
decreasing biochemical oxygen demand (BOD) decreases impact of sewage on the environment
BOD is the amount of O2 needed for microbial decomposition of the organic material in a sample
Grit chamber
Biological filter
Clarifier

26. Microorganisms in Sewage Treatment
if not treated the high BOD found in sewage could deplete the O2 level in the receiving water
in other words if raw sewage is deposited into a lake or stream without treatment, it would effectively suck the oxygen out of the water, leaving very little for the fish and other organisms

27. Microorganisms in Sewage Treatment
sewage treatment is a controlled process that strives to eliminate the excess organic material, thus diminishing the BOD
most of the removal of organic matter is done by microorganisms
bacterial filaments

28. Microorganisms and Water Treatment and Testing
municipal water supplies are tested and treated for the removal of pathogenic microorganisms and chemicals
this is done with the use of chemicals

29. Microorganisms and Solid Waste Treatment
the elimination of organic waste material can be enhanced by microorganisms
increase cost to separate organic material from inorganic (glass, metal, plastic)
composting: natural decomposition of organic solid materiel results in excellent fertilizer

30. Compost
microorganisms are needed to breakdown the organic material

31. Bioremediation: use of microorganisms to eliminate or make harmless pollutants in an environment
pollutants removed can include
organic solvents
toxic chemicals
hydrocarbons
oil spill

32. Bioremediation introduces specific organisms to the polluted area
many toxic substances are man-made/new to the environment (xenobiotics)
no time for naturally occurring microbes to have evolved biochemical pathways for their degradation
scientists are trying to develop new microbes for the degradation of environmental polluters
Cleaning an oil spill

33. Bioremediation
scientists are also making use of organisms already found in the environment
enhance their requirements for growth, such as nutrition or water availability
Bacteria in an oil spill

34. Why Bioremediation?
current methods of controlling some environmental polluters are incineration or storage in land fills, which result in
more pollution
health risks
bioremediation is
inexpensive
publicly accepted
non-polluting (ideally)
in situ treatment (at the site)