Transcript Biotechnology and the Environment: Microbial Ecology

Biotechnology and the
Environment
– describes everything that surrounds a
particular organism
 Environment
Soil,
air, water
Other organisms
Temperature, humidity, radiation
Environmental Biotechnology - the
development, use and regulation of
biological systems for remediation of
contaminated environments (land, air,
water), and for environment-friendly
processes.
Bioremediation - the use of microorganisms
to remedy environmental problems
Events
What
are the events that triggered the interest
in environmental biotechnology?
–Rachel Carlson’s Silent Spring (DTT)
In
the 1960s, rain distributed 40 tons of DDT
each year on England alone-incorporated in the
food chain and it has a 20 year life span.
–Love Canal
–Burning of a River
–Exxon Valdez in 1989
What do they all have in
common?
The
advent of the Industrial Revolution
– increase in products and waste
– people moved to the city
– increase in human population
Regulations were passed:
 Resource
Conservation and Recovery Act (1976)
 Must identify hazardous waste and establish
standards for managing it properly
 Requires companies that store, treat or
dispose to have permits stating how the
wastes are to be managed
 Record of its travels: Chain of Custody
 EPA initiates the Superfund Program (1980)
~Counteract careless and negligent practices
 Environmental Genome Project
~Study and understand the impacts of
environmental chemicals on human diseases
Waste
 Solid:
landfills, combustion-including waste-to
energy plants, recovery
– Dumping, slurries, open burning
 Liquid: septic: sewage treatment, deep-well
injection
 Gas: fossil fuels, chlorofluorocarbons
–anything that can explode, catch fire,
release toxic fumes, and particles or cause
corrosion
 Hazardous
Garbage Test
 Banana
Peel
 Wood Scrap/Sawdust
 Wax Paper
 Styrofoam Cup
 Tin Can
 Aluminum Soda Can
 Plastic Carton
 Glass Bottles
 0.5 Years
4 Years
 5 Years
 20 Years
 100 Years
 500 Years
 500 Years
 >500 Years

There is no waste in Nature:
 From
rocks and soil to plants and animals to
air and water and back again:
Recycled largely by
Microbes
Biogeochemical Cycles are a major
part of the recycling process




Carbon Cycle: The primary biogeochemical cycle
organic cmpds  CO2 and back
Nitrogen Cycle: proteins amino acids
NH3NO2-NO3-NO2-N2ON2 NH3 etc_
Sulfur Cycle: Just like the nitrogen cycle,
numerous oxidation states. Modeled in the
Winogradsky column
Phosphorous Cycle: Doesn’t cycle between
numerous oxidation states only soluble and
insoluble form
Carbon Cycle
CO2
Organic compounds
Nitrogen Cycle
cyanobacteria
N2
leguminous
decomposition
Fixation
ammonification
NO2Pseudomonas
Bacillus Denitrification
Paracoccus
NO3-
NH3
Nitrification
nitrosomas
NO2nitrobacter
Sulfur Cycle
SO2
Atmosphere
H2SO4
Organic sulfur
S
SO4
H2S
Phosphorous Cycle
Sea simple
Phosphates
Phosphate
rocks
Phosphates too complex
for plants to absorb
from the soil
Microbes Breakdown
complex compounds
Scientists Learn from Nature: 1980s
concept of Gaia –the total world is a living
organism and what nature makes nature can
degrade (bioinfalibility); only man makes
xenobiotic compounds
– Clean up pollution-short and long term
solutions (cost, toxicity, time frame)
– Use compounds that are biodegradable
– Produce Energy and Materials in less
destructive ways
– Monitor Environmental Health
– Increase Recovery of Minerals and Oil
 The
Bioremediation finds it’s place
 Companies
begin to specialize in cleaning up toxic
waste spills by using a mixture of bacteria and
fungi because cleaning these spills usually
requires the combined efforts of several strains.
 Biotechnologists begin engineering “super bugs”
to clean up wastes.
 However, there are many microorganisms in
nature that will degrade waste products.
 Example:
0
reduced
0
+1 -1
Na + Cl2  NaCl
oxidized
The Players: Metabolizing
Microbes
 Site
usually contains a variety of microbes (review
figure 9.5)
 Closest to the contaminant: anaerobes
 Farthest away: aerobes
 The most common and effective bacteria are the
indigenous microbes (e.g. Pseudomonas in soil)
 Fungus and algae are also present in the
environment and do a good job of “cleaning up”
chemicals (fungi do it better than bacteria)
Environmental Diagnostics
 A promising
new area of research involves
using living organisms to detect and assess
harmful levels of toxic chemicals.
Daphnia magna
Branched
Antennae
Compound Eye
Transparent
Thorax and
Abdomen
When healthy Daphnia are fed a sugar substrate (galactoside attached to a fluorescent marker), they
metabolize the sugar and fluoresce under UV light.
When Daphnia are stressed by toxins, they do not have the
enzymatic ability to digest the sugar and therefore do not
fluoresce under UV light.
 Toxicity
reduction involves adding chemicals to
hazardous waste in order to diminish the
toxicity.
– For example, if the toxicity results from
heavy metals, EDTA will be added to the
waste and the effluent will be tested again to
determine if the toxicity has been acceptably
reduced.
EDTA chelates (binds to) metals, thereby
making them unavailable to harm
organisms in a particular body of water.
Careers in Environmental Biotech
 Biodegradation
– Wastewater treatment plants, organic farming
 Bioremediation
– Environmental clean-up companies, labs developing super
bugs
 Biocatalysis
– Plastics, degradable and recyclable products
 Other
– Mining companies, oil companies