Title: Bacteria
1Bacteria VirusesHow they differ from us
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3Bacterias Negative Impact?
botulism
- Disease-causing
- Metabolize host
- Produce toxins
tuberculosis
4Compare bacteria cell to our cell
5List the main differences
- Eukaryotes
- Roughly (if a spherical cell) 10 times
the diameter 100 times the surface
area 1000 times the volume of a
prokaryote. - DNA is in paired chromosomesDNA is in a nucleus
contained in a membrane - Larger ribosomes
- Contain additional structures such as
Mitochondria Chloroplasts that
are "live-in" prokaryotes - Have additional structures to help with
cell organization and functioning
6Eukaryote Cell Structure
7- Prokaryotes
- About one tenth the size of a eukaryote
- DNA is a loopDNA floats in the cytoplasm
- Small ribosomes
- some are anaerobic (poisoned by oxygen)some can
live with oxygen or without itsome use oxygen - have a lot of biochemical diversity
8Bacterial Structures
- Flagella
- Pili
- Capsule
- Plasma Membrane
- Cytoplasm
- Cell Wall
- Lipopolysaccharides
- Teichoic Acids
- Inclusions
- Spores
9Shapes of Bacteria
- Coccus
- Chain Streptoccus
- Cluster Staphylococcus
- Bacillus
- Chain Streptobacillus
- Coccobacillus
- Vibrio curved
- Spirillum
- Spirochete
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12Flagella
- Motility - movement
- Swarming occurs with some bacteria
- Spread across Petri Dish
- Proteus species most evident
- Arrangement basis for classification
- Monotrichous 1 flagella
- Lophotrichous tuft at one end
- Amphitrichous both ends
- Peritrichous all around bacteria
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14Pili
- Short protein appendages
- smaller than flagella
- Adhere bacteria to surfaces
- E. coli has numerous types
- K88, K99, F41, etc.
- Antibodies to will block adherance
- F-pilus used in conjugation
- Exchange of genetic information
- Flotation increase boyancy
- Pellicle (scum on water)
- More oxygen on surface
15F-Pilus for Conjugation
16Capsule or Slime Layer
- Glycocalyx - Polysaccharide on external surface
- Adhere bacteria to surface
- S. mutans and enamel of teeth
- Prevents Phagocytosis
- Complement cant penetrate sugars
17Cell Wall Summary
- Determine shape of bacteria
- Strength prevents osmotic rupture
- 20-40 of bacteria
- Unique to bacteria
- Some antibiotics effect directly
- Penicillin
18Gram Staining
Bacteria are small and transparent so how to
see? Place a slide with a bacterial smear on a
staining rack. STAIN the slide with crystal
violet for 1-2 min. Pour off the stain.Note
fingers stain Gram-positive - use forceps! Flood
slide with Gram's iodine for 1-2 min. Pour off
the iodine. Decolourize by washing the slide
briefly with acetone (2-3 seconds). Wash slide
thoroughly with water to remove the acetone - do
not delay with this step. Flood slide with
safranin counterstain for 2 min. Wash with
water. Blot excess water and dry in hand over
bunsen flame. http//www.microbiologybytes.com/vi
deo/Gram.html
19Gram Stain Procedure
- Smear cells from 1 colony on slide (put pick in
alcohol) - Fix bacteria to slide by passing the bottom of
the slide through a flame 4 times. Cool - 2 drops Crystal Violet for 45 secs
- Rinse in tap water
- 2 drops iodine for 45 secs. Rinse with water
- Drip alcohol until runs clear
- Rinse with tap water
- 2 drops safranin for 30 secs then rinse
- Draw under high power label shape and gram type
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21Classify these
22Classify These
anthrax
23What is a Virus?
24They are space ships carrying alien genetic
material.
- The ship is made of protein
- Inside is either DNA or RNA
- They invade our cells or bacterial cells and
inject their DNA or RNA - Then the hijacked cells make new viruses and die
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26Yes, they can also be harmful
- Example Viral Infectious Diseases
- AIDS
- Chickenpox
- Common Cold
- Hepatitis
- Herpes simplex
- Infuenza
- Mononucleosis