Prokaryote and Metabolism

1
Prokaryote and Metabolism

• Found everywhere
• More bacteria in mouth than the total number of
  people who have ever lived.
• Minority that cause disease
• Bubonic plague
• TB
• Cholera
• STDs
• Food poisoning
• Beneficial
• Carbon cycle
• Decomposers
• Symbiosis (mitochondria)

2
Traditional 5 Kingdom System

• Kingdom Monera
• All prokaryotes
• Based on structural difference b/w proK and euK
• By comparing RNA w/ sequence of genomes
• Two major branches of proK
• Bacteria
• Archaea

3
Development of Domains

• Domain Archaea
• Antiquity
• Extreme environments
• Like early earths

• Domain Bacteria
• Modern organisms
• Current environment

4
Structure and Function

• Shapes
• Cocci
• Bacilli
• Helical

• Cell wall outside of plasma membrane
• Peptidoglycan Gram Positive (AB sensitive)
• LPS Gram Negative (AB insensitive)
• Capsule sticky secretion, protective layer,
  adhere to substratum

5

• Motility
• Pili surface attaching device

• Flagella movement, differs from eukaryotes
• Not part of cell membrane

• Slime trails, taxis

6
Reproduction Adaptation

• Transformation proK cell takes up genes from
  surrounding environment. Genetic Transfer b/w
  proK cells. Cross species

• Conjugation direct transfer of genes from one
  cell to another

• Transduction virus helps to exchange genes b/w
  cells

7
Metabolism

• Photoautotrophs cyanobacteria
• Chemoautotrophs stone eaters/oxidizers
• Photoheterotrophs
• Chemoheterotrophs

• Saprobes
• Parasites

• Relationship to O2
• Obligate aerobe
• Facultative anaerobes
• Obligate anaerobes

• Photosynthesis

8
Environments

• Extremophiles extreme environments

• Methanogens methane producers, swamps, obligate
  anaerobes

• Extreme Halophiles

• Extreme Thermophiles

9
Ecological Impact

• Symbiotic relationship w/ host organism
• Mutualism both benefit
• Commensalism one benefites, no harm to other
• Parasitism harm to host
• Opportunistic
• Koshs Postulates
• Exotoxins secretes proteins
• Endotoxins part of cell wall
• Opportunistic normal residence of host, but can
  cause illness when host immune is weaken

10
Kochs Postulates

• ID Antrax and Tb bacteria (1800s)
• Developed guidelines to determine agent.
• Still used today

1. Find same pathogen in each diseased individual
2. Isolate the pathogen from a disease subject and
   grow (pure culture)
3. Induce disease in experimental animals by
   transferring cultured pathogen.
4. Isolate SAME pathogen from experimental animals

11

• Exotoxins
• Proteins secreted by bacteria
• Clostridium botulinum exotoxin produces disease
  botulism. 1grams could kill a million
• Vibrio cholera cholera
• E. coli travelers diarrhea
• Endotoxins
• Components of outer membrane
• Gram negative
• Salmonella typhi typhoid fever
• Bioremediation
• Use of organisms to remove pollutants from water,
  air, and soil

12
The Nasties

• necrotizing fasciitis

• syphillus

• Gonorrea

• Clyamidia

• Leprosy