Transcript II. Kingdom Eubacteria

Bacteria
Lab Biology
Chapter 23
Mrs. Nemanic
I. Kingdom Archaebacteria
A. Characteristics


Live in extreme environments
Cell membrane and cell wall different than
others
B. Groups
1. Methanogens
a. Anaerobic - don't require O2 (anaerobic
respiration)
b. Produce Methane gas
2. Halophiles
a. High salt environment
b. Use salt to make ATP
3. Thermoacidophiles
a. Extreme acid and hot temperatures
II. Kingdom Eubacteria
A. Characteristics
1. Grouped by Shapes

a.
b.
c.
Bacilli - rod
Cocci - sphere
Spirilla - spiral
II. Kingdom Eubacteria
A. Characteristics
2. Grouped by arrangement:
a.
b.
c.
"Strepto" - chain
"Staphylo" - cluster
"Diplo" - pairs
II. Kingdom Eubacteria
A. Characteristics
3. Grouped by Gram Staining :
a.
Gram Positive
*Retain purple stain
*Thicker layer of Peptidoglycan
b.
Gram Negative
*Pink stain
4. Grouped by how they obtain food
II. Kingdom Eubacteria
B. Phyla
1.
Phylum Cyanobacteria
a.
b.
Photosynthetic
Blue-green algae
c.
Heterocysts - cells that "fix" N2
(convert it into a molecule)
II. Kingdom Eubacteria
B. Phyla
2.
Phylum Spirochetes
a.
Spiral-shaped
b.
Move by cork-screw motion
c.
Tremponema pallidum - syphilis
II. Kingdom Eubacteria
B. Phyla
3. Phylum Gram-Positive
a.
b.
c.
d.
Streptococci - causes strep throat
Yogurt- made by bacteria in milk
Lactobacillus - tooth decay
Actinomycetes - produce antibiotics
II. Kingdom Eubacteria
B. Phyla
4. Phylum Proteobacteria
a.
Enteric bacteria - live in intestines
1. Escherichia coli (e. coli) - produces Vitamin K
and helps digestion
2. Salmonella - in chicken intestines, food poison
b.
Chemoautotrophs - oxidize chemicals for
energy - nitrogen fixing (Rhizobium)
III. Structure
A. Cell wall
1. Eubacteria cell walls made of
peptidoglycan.
a. Gram negative eubacteria's lipid layer
prevents some antibiotics from entering.
B. Cell Membrane & Cytoplasm
1. Lipid bilayer
2. Prokaryotes - no membrane-bound
organelles
3. Bacteria are the only prokaryotes
III. Structure
C. Capsules
1. Outer cover of polysaccharides
2. Protection against:
a. drying
b. harsh chemicals
c. white blood cells
3. Glycocalyx - a capsule of sticky sugars
that enables bacteria to attach to host
cells
III. Structure
D. Pili
1. Short, hair-like, protein structures on
surface of some bacteria
2. Adhere to host cell; transfer genetic
material between bacteria
E. Endospore
1. Dormant structure with thick protective
covering produced during harsh
environmental conditions.
III. Structure
F. Structures for Movement
1. Flagella
2. Slime – to glide over
3. Spiral shaped bacteria move in corkscrew rotations.
IV. Nutrition
1. Heterotrophs – get nutrients from
organic matter
a. Saprophytes – feed on dead, decaying
matter
2. Autotrophs – obtain energy from
sunlight or minerals
a. Photoautotrophs – use sunlight for energy
b. Chemoautotrophs – obtain energy from
inorganic compounds, oxidize chemicals
V. Reproduction
1. Binary fission - asexual cell
division of prokaryotes that produces
identical offspring.
VI. Growth
1. Bacteria require certain temperatures
and pH.
2. Obligate Anaerobes – cannot survive in O2
a. Ex: Clostridium tetani – causes tetanus.
3. Facultative anaerobes – live with or without
O2
a. Ex: E. coli
4. Obligate aerobes – cannot survive
without O2
VII. Genetic Recombination
1. Transformation – bacterial cell takes in DNA
from external environment
2. Conjugation – genetic information is
exchanged between two bacteria
3. Transduction – a virus obtains some
bacteria DNA after viral replication & carries
it to the next host cell.
VIII. Bacteria & Disease
1. Toxins – poisons that cause disease
A. Antibiotics – drugs used to fight bacteria.
Obtained from bacteria and fungi.
1. Penicillin – interferes with cell-wall synthesis
2. Tetracycline – interferes with protein
synthesis
3. Sulfa Drugs – inhibits metabolism
4. Broad-Spectrum Antibiotics – affect a wide
variety of organisms
VIII. Bacteria & Disease
B. Antibiotic Resistance
1. Some mutant bacteria may resist antibiotics.
Thus, they survive, reproduce, and make
disease more difficult to treat.
C. Useful Bacteria
1. Decomposers – decay organic material
2. Food production
3. Clean up oil spills
4. Genetic Engineering and Medicines