By: Nicole Layton

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Biofilms

• By Nicole Layton
• Amber Stike
• Brittany McElwee
• Mary Biltz

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1) The majority of microorganisms live in large
numbers, attached to a surface.
2) Biofilms are formed in layers,clumps, and
ridges. Sometimes they form into mushroom like
structures or stalks. One or more species of
microorganisms are bounded together by a matrix
to form EPS.
3) The matrix that binds species together is made
of polysaccharides, DNA, and protein.
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4) Another name for slime is extra-cellular
polymeric substance.
5) A synergistic interaction is a transfer of
genetic material between microbes.
6) Three synergistic interactions in biofilms are
shelter from changes in the environment, sharing
of metabolic by-products, and increased tolerance
to antimicrobials.
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7) Antonic Van Leeuwenhoek is credited with the
first discovery of biofilms.
8) Food particles that are stuck to the EPS form
microscopic niches, each with their own
microenvironment, that allows microorganisms with
different needs to come together and form
diverse microbial consortium
9) Hydrogel is a biofilm matrix, a complex
polymer hydrated with many times its dry weight
in water (EPS). The hydrogel characteristics of
slime confer fluid and elastic properties that
allow the biofilm to withstand changes in fluid
shear within its environment.
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10) EPS(or hydrogel) help the biofilm withstand
changes in the environment, so one way of
withstanding the changes is forming the streamers
(gooey assemblages of microbes tethered to a
surface).
11) Environmental biofilms can produce sulphuric
acid and corrode pipes causing leaks. Biofilms
can also contaminate water causing serious human
illness.
12) Certain biofilms can be found in cattle feed
and help cattle by preventing disease and
breaking down toxic wastes in water.
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14) Some biofilms are heavily populated with
bacteria, which help convert sulfate or sulfuric
acid, a contaminant that is associated with
mining of metal ores and zinc from ground water
into zinc sulfide.
13) A methanogen are archea whose actions
accelerate the growth of the bacterial community
and are responsible for flatulence.
15) Biofilms have greatly increased the price of
oil due to the corrosion and 16 mile replacement
of a pipeline in Alaska.
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16) Advantages that biofilms on plants give to
individual cells are protection from the
environment such as wind and desiccation etc. and
it enhances a microorganisms resistance to
antimicrobial substances.
17) Two functions of plants for the biofilms that
live with them are that the plants serve as a
mechanical support and that the plant can provide
some nutrients for the microbes in the biofilm.
18) Pseudomonas fluorescens helps the plants it
lives with by colonizing roots and producing
antibiotics that exclude fungi, protecting plants
from pathogens.
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19) Mycorrhizal fungi form a broad network in the
soil around a plants roots while imbedding
itself into the roots cells. This creates a wide
surface area that the plant will use for water
and nutrient absorption.
20) Quorum Sensing is a defense mechanism that
is enabled by a biofilm for intercellular
signaling. Quorum sensing effects humans health
by being involved in the defense of antibiotics.
21) A persister are specialized survivor cells,
that slow growing variations that exist in every
bacteria population. It drives bacterial cells
into a dormant state by generating the toxin
role, but it has a reduced growth rate, and
slowed cell division decreases fitness of the
population.
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Bibliography

• Websites
• http//en.wikipedia.org/wiki/Methanogens
• http//jeffp.myweb.uga.edu/harmful.html
• http//www.lpb.org/education/classroom/itv/enviro
  tacklebox/teacherguide/module1/tbio.htm
• http//www.billingsgazette.com/newdex.php?display
  rednews/2004/11/10/build/health/40-msub-grants.in
  c
• http//www.newswise.com/articles/view/524258/?sc
  rsla

Booklet Ceri, Howard, Harrison, Joe J., Marques,
Lyriam L. R., and Turner, Raymond J. 2005.
American Scientist