2. The Prokaryotic Groups
◦ Prokaryotes are
divided into two
groups
◦ Bacteria
◦ Archaea
◦ See difference on
Page 291 figure
10.6
3. The Proteobacteria
◦Includes most G(-) bacteria and are thought to
have arisen from a common photosynthetic
organism
◦Largest group of bacteria
4. Alphaproteobacteria
◦ Typically can grow at a low
level of nutrients
◦ Unusual morphology including
buds or stalks
◦ Stalks that are used to adhere to
a surface are called
prosthecae
5. ◦Name comes from the
mythological Greek god
Proteus who could morph into
many shapes
◦ Alpha◦ Beta◦ Gamma◦ Delta◦ Epsilon-
6.
7. ◦ Alpha- are very important in
agriculture because many
of these bacteria can fix
nitrogen and can live in
symbiosis with plants and
humans
Azosprillium
8. ◦Rickettsia and Chlamydia
are obligate intracellular
parasites
◦They can only reproduce
within a mammalian cell
◦They are commonly
transmitted within insect
bites and ticks
◦ Spotted fever, typhus, Rocky
Mountain spotted fever
9. ◦ Caulobacter bacteria are found
in low-nutrient aquatic
environments
◦ They have prosthecae because
of the constant changing flow of
water
10. ◦Bartonella is a gram (-) bacillus that causes
cat scratch fever
11. Betaproteobacteria
◦There are many similarities
between alpha- and beta◦Often use ammonia,
hydrogen gas, or methane
◦Pathogenic bacteria are
considered
betaproteobacteria
12.
13. ◦Spirillum is found in fresh water and has
polar flagella and is an aerobic organism
14. ◦ Sphaerotilus are sheathed,
G(-) bacteria found in
sewage
◦ The sheath is a protective
layer which provides
protection and a source of
nutrient accumulation
15. ◦Bordetella is the group of bacteria responsible for
whooping cough. It is nonmotile, aerobic, and
G(-)
16. ◦Neisseria are aerobic,
G(-), cocci that live in
mucosal membranes
of mammals
◦Pathogens in this groups
cause gonorrhea and
meningitis.
18. ◦ Pseudomonas is aerobic, G(-) rods with
polar flagella
◦ Very common in soil
◦ Infects urinary tract, burns, wounds
◦ Some species have evolved to grow
inside some antiseptics
28. Gram Positive Bacteria
◦Can be divided into two groups
◦High G+C ratio
◦Low G+C ratio
◦G = guanine
◦C = cytosine
DNA
29. Research
◦ Where does the bacteria live?
◦ Shape or arrangement?
◦ Disease it causes (if it does)?
◦ Growth conditions?
◦ Interesting fact?
◦Clostridium
◦Epulopiscium
◦Staphylococcus
◦Lactobacillus
◦Listeria
◦Propionibacterium
◦Leptospira
◦Fusobacterium
39. ◦Cell walls lack peptidoglycan (like eukaryotes)
◦Halophiles- organisms that can survive a high
salt content
◦Methanogens- organisms that produce
methane
◦Hyperthemophiles- organisms that can survive
and thrive in high temperatures
41. ◦Though many prokaryotes have
been discovered, scientists have
hardly reached the tip of the
iceberg when it comes to
discovering the vast number of
organisms still out there
◦Maybe YOU will be the next
scientist to discover a new
bacterium!
