Download Helpful and Harmful Bacteria

Helpful and Harmful
Bacteria
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Helpful and Harmful Bacteria
S Contrary to popular belief that most microorganisms are
harmful, the usefulness of bacteria far outweighs the
damage that they do!
S Used in food, waste management, health and even clothing.
Helpful Bacteria
S Recyclers
S Pollution Control
S Probiotic Agents
S Industry
Recyclers
S Many bacteria are saprophytes.
S Saprophytes release enzymes to breakdown materials
around them for other organism to consume. 
Causing Decay
S Involved in Compost production
Pollution Control
S Bioremediation: process that uses microorganisms to
destroy, transform, or immobilize environmental
contaminants
S Examples of bioremediation projects can include oil spills and
soil cleaning
Probiotic Agents
S Probiotics- means “for life”
S Help maintain health and has potential to help prevent disease
Industry
S Bacteria make many enzymes that are useful in industrial
processes
S Bacteria are used in the production of consumer products:
vinegar, lactic acid, dairy products (cheese, yogurt),
antibiotics
Harmful Bacteria
S Bacteria are best known for causing disease
S Bacillus anthracis was the first bacterium proven to cause disease
S Well-known plagues
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Diphtheria
Typhoid fever
Bubonic plague (Black Death)
S Other illnesses: Strep throat (Streptococcus), Stomach ulcers (H.
pylori), etc
Walkerton, Ontario E.coli
Outbreak
S On May 12, 2000, heavy rains washed fecal bacteria
from cattle manure into well water near the town of
Walkerton, ON
S Within 10 days, hundreds of residents had symptoms
of E. coli poisoning
S Symptoms include: vomiting, cramps, bloody diarrhea, fever
S By May 22, the first death directly linked to E. coli was
confirmed
Escherichia coli
S There are hundreds of types of E. coli bacteria and not
all are dangerous
S E. coli are important in intestines of animals and in digestion
S E. coli O157:H7 produces a toxin (poison created from a living
organism)
E-coli
S E.coli can spread through:
S Ground beef, unpasteurized milk, contact with cattle, drinking
inadequately chlorinated water, swimming in contaminated
lakes or pools
S This event led to Government legislation on the testing
and treatment of drinking water
S 17 deaths, 2300 illnesses
Antibiotics
S Natural substances that immobilize or destroy microorganisms
by attacking metabolic pathways in the bacteria but not the
host
S Ex. Penicillin, streptomycin
S 2500 naturally occurring antibiotics
S Strains that survive reproduce and pass on resistance
S Many human pathogens are now resistant