Week 15: Microbiology - antibiotics

• Bacteria: Mycobacterium tuberculosis (TB)
• •Fungi: Candida albicans (Thrush)
• •Viruses: Zaire ebolavirus (Ebola)
• •Protozoa: Plasmodium falciparum (Malaria)
• •Algae: Protothecia wickerhamii (Protothecosis)
• •Some viroids and prions are single molecules
• • Chloroplasts are the same size as prokaryotic cells, divide by binary fission, and, like bacteria, have Fts proteins at their division plane.
  • Have their own DNA that is circular not linear.
  • Have their own ribosomes that are 30S and 50S.
• • The mitochondria are the same size as prokaryotic cells, divide by binary fission, and the mitochondria of some protists have Fts homologs at their division plane.
  • Mitochondria have their own DNA that is circular not linear.
• Gram-positive bacteria have thick peptidoglycan layers with teichoic acids attached to them, while gram-negative bacteria have thin peptidoglycan layers without any attachments.
• Symbiogenesis (or endosymbiotic theory): Theory that eukaryotic cells evolved from symbiosis of single celled prokaryotes about 1.5 billion years ago.
• light microscope:

  •Magnification= 1000x

  •Resolution=0.2µm

  •Oil immersion= Reduce light scattering
• •Transmission (TEM):

  • Sample sectioned
  • Freeze fracture
  • 60nm slices
  • 100,000x0.2nm resolution
• Scanning (SEM):

  • 100,000xSurface only
• •The Gram-stain~

  1.Preparation of smear

  2.Heat-fixing on slide

  3.Staining

  4.Microscopy
• Steps for gram +ve stain:
• gram positive= purple

  gram negative= pink

  
• Stromatocytes fossils are made up of layers of what type of bacteria?

  Cyanobacteria
• what organism did robert hook first observe and describe?

  fungi
• what are the three postulates of Koch's postulates?

  1. Association 2. Isolation 3. Reproduction
• cocci/coccus= round microorganisms