Environmental Protection
Essential Idea: Biotechnology can be used in the
prevention and mitigation of contamination from
industrial, agricultural and municipal wastes.
TOK

Emergent properties are the outcome of the
interaction of the elements of a system. In what
context is a reductionist approach to science
productive and in what context is a reductionist
approach problematic?
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Bioremediation

In response to environmental pollution
incidents, various methods of cleanup can be
employed.
Bioremediation
 Physical and Chemical procedures.

Bioremediation

Various physical and
chemical means are
often used to clean
up a polluted area.
Detergents
 Pressure washers

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Bioremediation

Physically scrubbing
polluted areas with
chemicals can also
be used during clean
up.
http://www.maritimejournal.com/news101/pollution-control/put-bioremediation-into-pollution-toolkit
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Use of Microorganisms

Microorganisms are
often used in
bioremediation.
http://biologybiozine.com/articles/unit-8-animals/the_loss_of_biodiversity-php
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Bioremediation--How it Works


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Generally, some toxic substance is spilled into
the environment.
The waste kills most bacteria, but a few survive.
The bacteria which survive can be cultured and
used to break down the waste.
Bacteria can also be engineered to break down
the waste by inserting the correct gene/plasmid
into the genome of the bacterium.
Bioremediation

The bacteria may change the waste into
something less toxic, into smaller parts, or break
it down completely.
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Bioremediation-Examples:

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
When oil is spilled, it poses
many challenges for cleanup.
Benzene and other types of
polycyclic aromatic
compounds are found the spill.
The tendency for the oil to bind
tightly to soil particles poses
challenges for cleanup.
It throws off the carbonnitrogen balance and hinders
microbial growth.
http://www.tanushchem.com/benzene.htm
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Bioremediation-Examples:

Certain genera of bacteria, such as Marinobacter
and Pseudomonas are often used in the cleanup
efforts.

Marinobacter hydrocarbonoclasticus is a genus of
proteobacteria found in sea water and readily
degrades oceanic oil spills which often included
aromatic compounds like benzene.
Both images: https://microbewiki.kenyon.edu/index.php/File:Screen_shot_2012-1214_at_11.23.24_AM.png
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Bioremediation-Examples:

Some members of the
Pseudomonas genus
such as Pseudomonas
aerugnosa and P.
putida are used to
metabolize
hydrocarbons found
in oil spills.
http://www.agriculture.gov.bb/agri/index.php?option=com_content&view=article&id=704:amazing-and-interesting-bacteria-part2&catid=140:analytical-services&Itemid=132
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Bioremediation-Examples:

Methyl mercury is a common environmental
pollutant from industry and can be broken
down by many Pseudomonas species such as P.
putida. The remaining mercury can be collected
and removed from the environment.
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Biofilms


According to the IUPAC, a biofilm is an
aggregate of microorganisms in which cells that
are frequently embedded within a selfproduced matrix of extracellular polymeric
substance (EPS) adhere to each other and/or to
a surface.
EPS is a sugary, molecular strand that helps to
develop complex 3D structures. This makes the
biofilm stronger and enables it to survive.
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Biofilms

Biofilms possess emergent properties:


Initial attachment:
Growth:
 Irreversible attachment:
 Maturation I:
 Maturation II:

Dispersion:
http://www.biofilm.montana.edu/node/2390
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Initial Attachment
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The formation of a biofilm begins with the
attachment of microorganisms to a surface.
Initially these attachments are weak and
reversible, due to Van der Waals interactions.
http://www.biofilm.montana.edu/node/2390
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Irreversible Attachment

Later the attachment becomes more permanent
as bacterial structures such as pili get involved
in the attachment.
http://www.biomedcentral.com/1471-2180/10/57/figure/F6?highres=y
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Maturation I

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Cells of the biofilm communicate with other
cells via quorum sensing.
Quorum sensing is known to be involved in the
formation of a biofilm in numerous bacterial
species.
http://www.biofilm.montana.edu/node/2410
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Maturation II


Once colonization has
begun, the biofilm grows
through cell division and
recruitment of other
bacteria.
Most biofilms are diverse
mixtures of many species
of bacteria, fungi, algae,
yeasts, protozoa, and
many other
microorganisms.
https://microbewiki.kenyon.edu/index.php/File:Microbes_in_stream_biofilms.jpg
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Maturation II
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Additionally, this stage is also characterized by
the growth of polysaccharide matrices and
inclusion of materials from the surrounding
environment.
These matrices act as an enclosure for the
biofilm and increase the resiliency of the
structure.
http://medcraveonline.com/JMEN/images/JMEN-01-00014-g002.png
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Dispersion
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Dispersion is the final stage of the formation of
a biofilm.
During this stage, the biofilm is well established
and only changes in shape and size.
This stage allows the colony to spread to new
surfaces.
http://www.biofilm.montana.edu/node/2390
Ubiquity of Biofilms
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
Biofilms are ubiquitous, and are very important
to the health and well being of the economy,
and the people who live in it.
Biofilms cost our economy billions of dollars
each year.

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Energy loss
Equipment damage
Product contamination
Medical infections
https://www.biofilm.montana.edu/resources/images/biofilm-general-interest/biofilms-impact-human-health-and-industries.html
Ubiquity of Biofilms
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Microorganisms growing in a biofilm are often
highly resistant to antimicrobial agents.
Biofilms have properties that differ quite a bit
from the free-floating bacteria that comprise
them.
The dense extracellular matrix and outer layer
of cells acts to protect the cells in the interior.
Horizontal gene transfer between organisms
facilitates a stable, more resilient biofilm.
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Ubiquity of Biofilms


Not all biofilms are more resistant to
antimicrobials.
Some biofilms show just as much susceptibility
to antimicrobial agents as free-floating bacteria.
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Biofilms in Bioremediation

Biofilms offer a huge potential for helping to
clean up environmental damage, hazardous
waste clean up, and wastewater treatment.
http://www.slideserve.com/kurt/bioremediation-and-biofilms
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Biofilm and Wastewater
Treatment


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Biofilms play an
important role in
wastewater
treatment.
Trickle filter beds are
often built to
facilitate the
formation of a
biofilm.
The biofilm feeds off
of the nutrients in the
waste stream.
https://powersoregonsewer.files.wordpress.com/2013/03/2013-wwtp-trickling-filter.jpg
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Environmental Problems and
Biofilms

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For all the good that biofilms
do, there are many problems
they can cause.
They can clog or corrode
pipes.
They can contaminate
surfaces of food production
facilities.
They can contaminate
waterways through the
transfer of ballast water from
ships.
http://trustwater.com/markets/hospitality/biofilm-removal/
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