PROKARYOTES
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WHAT WE NEED TO LEARN!
 Key
characteristics of members of the
kingdom archaebacteria and kingdom
eubacteria
 Structure (how they are built)
 Type of nutrition and growth
 Bacteria and disease
 Useful bacteria
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KINGDOMS OF BACTERIA
Two main groups the Archaebacteria and the
Eubacteria
 What do we already know about these?

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ARCHAEBACTERIA
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Extreme Bacteria
ARCHAEBACTERIA CHARACTERISTICS
 3.5
billion years old
 Live in extreme conditions
 Nonpathogenic
 Differ from eubacteria


Cell membranes are built from different
types of fats
Cell walls are built from different
carbohydrates than the eubacteria.
 There



are three main groups
Methanogens
Extreme halophiles
Extreme thermoacidophiles/thermophile
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EUBACTERIA
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True Bacteria
EUBACTERIA CHARACTERISTICS - ENERGY
Eubacteria get their energy and nutrition in
many different ways
 Aerobic and anaerobic
Anaerobes is any organism that does not require
oxygen for growth ex. Clostridium butyricum
 Aerobes require oxygen

 Producers
 Photosynthetic
 Chemosynthetic
 Consumers
 Symbiotic
 Parasitic
 Saprophytic
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GENERAL CHARACTERISTICS OF BACTERIA

Bacterial shapes
Bacillus – rod shaped
 Coccus- spherical
 Spirilla – corkscrew
 Staphylococci – clusters of cocci bacteria
 Streptococci- chains of cocci bacteria


Reproduction

asexually by binary fission
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BINARY FISSION

http://www.youtube.com/watch?v=DY9DNWc
qxI4
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STRUCTURE OF BACTERIAL CELLS
 Smaller
than plant and animal cells
 Have cell membranes that surround
their cytoplasm
 Inside the bacterial cells there is a
chromosome, ribosomes and sometimes
an extra circular piece of DNA called a
plasmid
 No cell membrane-bound organelles
(prokaryotic)
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OTHER FEATURES OF BACTERIA
Endospores- some bacteria are able to
produce spores that are capable of
withstanding harsh conditions.
 Motility- some bacteria move by use of a
flagella. Some spiral shaped bacteria move by
a corkscrew motion, others can contract and
slide along ex. Myxobacteria
 Some eubacteria are pathogenic

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E. COLI MOVING

http://www.youtube.com/watch?v=2P9hvlsF9_
c
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TYPES OF EUBACTERIA
Eubacteria can be divided into at least 12
phyla’s, we will look at 4
 First 3 major divisions based upon cell wall
1. Mycoplasma
 No cell wall
 Smallest microorganisms capable of
independent growth.
 Some are pathogenic causing pneumonia
in humans and cattle

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2. Gram positive bacteria
 Thick cell walls
 Widespread in soil and air
 Used in the preparation of food products
such as sauerkraut, buttermilk, and yogurt
 Some are a source of antibiotics
 Responsible for tooth decay
3. Gram Negative bacteria
 Thin Cell wall -Tend to be antibiotic
resistant
 Responsible for strep throat
 Many are photosynthetic and anaerobic
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4. Cyanobacteria
 Blue/green bacteria – photosyntheticcontain chlorophyll but it is not in a
chloroplasts
 Aerobes
 Can cause green color in polluted lakesbloom
 Helped put oxygen in primitive
atmosphere
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PATHOGENIC BACTERIA
 Some
eubacteria cause disease
 Enter the body in a number of ways
 Some produce toxins
 Bacterial infections can be treated with
antibiotics(cure) and
vaccines(preventative)
 Safety of the foods we eat have
improved due to pasteurization,
radiation, canning, refrigeration, FDA,
etc
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BENEFICIAL BACTERIA
 Some
Why?

bacteria produce antibiotics.
Answer: Antibiotics inhibit the growth of
other rival bacteria
 Bacteria
are decomposers –
saprophytes.

They recycle nutrients and rid our world of
dead material. ex. nitrogen and carbon
 Some
bacteria can be used to clean up
environmental pollutants and wastebioremediation – ex. Oil spills
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BENEFICIAL BACTERIA (CON’T)
 Help
produce some of the foods we eat
such as yogurt, sour cream, cheese,
sauerkraut, sugar syrups…..
 Used in the production of medicines,
enzymes, cleansers and adhesives.
 Methane produced by bacteria is used
as fuel.
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