Environmental Protection

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?

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 4

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

Use of Microorganisms • Microorganisms are often used in bioremediation. http://biologybiozine.com/articles/unit-8-animals/the_loss_of_biodiversity-php

Bioremediation--How it Works • 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.

Bioremediation-Examples: • 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 carbon-nitrogen balance and hinders microbial growth. http://www.tanushchem.com/benzene.htm

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_2012-12-14_at_11.23.24_AM.png

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-part-2&catid=140:analytical-services&Itemid=132

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.

Biofilms • According to the IUPAC, a biofilm is an aggregate of microorganisms in which cells that are frequently embedded within a self-produced 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.

Biofilms • Biofilms possess emergent properties: • Initial attachment: • Growth: • Irreversible attachment: • Maturation I: • Maturation II: • Dispersion: http://www.biofilm.montana.edu/node/2390

Initial Attachment • 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

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

Maturation I • 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

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

Maturation II • 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

Dispersion • 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 • 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. • 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 • 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.

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.

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

Biofilm and Wastewater Treatment • 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

Environmental Problems and Biofilms • 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/

Environmental Protection