Download Bacteria Notes

Domain Bacteria and Domain
BASIC
CHARACTERISTIC of Both:
Archaea
•Unicellular
•Heterotrophic or Autotrophic
•Prokaryotic
Bacteria:
Archaea
(salt)
- Halophiles
Eubacteria
“True Bacteria”
•
Archaea “Ancient”
- extremophiles
- Thermophiles,
- Methanogens
(anaerobic waste removal) (Hydrothermal
vents)
How do Bacteria and Archaea differ?
 Domain Bacteria
 Structural:
 Peptidoglycan in
cell wall
 Molecular:
 Simple RNA
polymerases
• Domain Archaea
• Structural:
• No
peptidoglycan in
cell wall.
• Molecular:
• Complex RNA
polymerase
 Gram staining is used to identify bacteria.
– Stains the peptidoglycan layer.
– Gram-positive = Stain color - purple, Thick
peptidoglycan cell wall
– Gram-negative = Stain color - Pink, Thin
peptidoglycan cell wall + outer membrane.
B.subtilis
E. coli
Gram-negative bacteria have a thin layer of
peptidoglycan and stain red/pink.
Gram-positive bacteria have a thicker
peptidoglycan layer and stain purple.
 Basic Bacterial Structure
pili
cell
membrane
Nucleic Acid
cell wall
Ribosome
Plasmid
flagellum
Bacteria are Classified by Shape and
Growth Pattern
– Bacillus = rod shaped
– Spirilla = spiral shaped
– Coccus = spherical shaped
- Diplo = pair
- Strepto = chain
- Staphylo = cluster
Test yourself…Classify these bacteria?
Diplococcus
Spirillus
Streptococcus
Streptobacillus
Genetic Variation in Bacteria
Transformation – Bacterial picks up free DNA and adds it in to its own
DNA.
Conjugation –One bacteria transfers DNA to another.
Mutation – Random change in a DNA sequence.