Download Important Bacterial Groups

Important Bacterial
Groups
In addition to being classified by Gram staining and
shape, bacteria are also classified by biochemical
properties and evolutionary relationships.
Proteobacteria
 Largest and most
diverse group
 Several subgroups
w/ varying nutritional
needs
 Aerobic and
anaerobic
Many live in symbiotic relationships with other
organisms.
Proteobacteria cont.
 Nitrogen-fixing bacteria live in
nodules on the roots of
legumes (beans, alfalfa, clover
etc.)
 Atmospheric nitrogen is not in a
form usable to plants; without
these bacteria plants could not
make nitrogen
Proteobacteria cont.
 Agrobacterium-




causes tumors in
plants
Rocky Mountain
Spotted Fever
Stomach ulcers
E. coli- live in
digestive tract
Salmonella- food
borne illnesses
Rocky Mountain Spotted Fever
 …carried by ticks
Gram-Positive Bacteria
 Very large group
 Includes bacteria that cause strep throat
 Botulism
 Members of the genus Lactobacilli used to make
yogurt
 anthrax
Anthrax- a biological weapon
Gram-positive bacteria that grow in
soil are used to make antibiotics
 What color do they
stain?
Why?
Cyanobacteria
 A.k.a blue-green




algae
Photosynthetic
Very numerous
Contribute to oxygenrich atmosphere
Food source to marine
animals
Spirochetes
 Gram negative
 Spiral-shapted
 Aerobic or anaerobic
 Corkscrew rotation
 Pathogens or free living
 Syphilis
 Lyme Disease
Chlamydia
 Gram negative
 Only live inside animal cells which supply them
with nutrients and protection
 no peptidoglycan
Can lead to inability to have children
Sometimes no symptoms are observed
Can be passed from mother to child