Monday, August 25, 2008
Modern Taxonomy
Modern Taxonomy
Whitaker's five Kingdom System 1969
Monera | Bacteria (prokaryote) |
Protista | Protozoa, algae |
Fungi | Molds, yeast |
Animalia |
|
Woese's 3-Domain System 1990
- Archaea
- Eubacteria
- Eukarya
Archaea
Eubacteria
Historical Foundations of Microbiology
1600's | Illness/death was considered as a sing, miasma | |
1700's | Microscope-animalcules | |
Spontaneous generation | Abiogenesis | |
Biogenesis | In order to have offspring you need al ivng thing | |
Tuskegee Project- Syphilis/1932-1972
Poor black people were lied that they received medical treatment when they weren't infected. Their feedings (sons and daughters) also become infected with syphilis.
History of Microbiology
- Early History ~1700
Microscope - van Leeuwenhoek
Biogenesis- Redi, Pasteur
- Golden Age (1879 - 1900)
Fermentation and Pasteurization-Pasteur
Germ Theory Disease- Pasteur and Koch
Aseptic Techniques- Semmelweis and Lister
Vaccination- Pasteur and Jenner
- Antimicrobial Therapy 1900's
Chemotherapy - Ehrlich
Antibiotics- Fleming
- Modern development + concerns
Antoine van Leeuwenhoek 1632-1723
Dutch Linen merchant
First to observed living microbes
Single- lens magnified up to 300x
Louis Pasteur 1822-1895
Showed microbes caused fermentation and spoilage
Disapprove Spontaneous generation
Developed pasteurization
Demonstrated "Germ Theory of Disease"
Developed rabies vaccine
Leeuwenhoek medal 1895
Jenner Edward
Develop the vaccine for small pox
Robert Koch 1843-1910
Koch's postulates; a sequence of experimental steps that verified the germ theory
Identified cause of anthrax, TB and colera
Developed pure culture methods.
Nobel Prize in 1905 discoveries TB
NOTE: He used gelatin to cultivate anthrax but it didn't work and he used something made by plants. Anthrax couldn't grow on gelatin because it is an animal disease. Gelatin was made from bones and junction of animals
Antimicrobial Agent
Erhlich 1910
Chemotherapy
Syphilis "magic Bullet"
Salvarsan
Nobel Prize 1908 for immunity
NOTE: Penicillin was mass market in World War II. Streptomycin (TB) was develop by Waksman from Rutgers
Aseptic Techniques
Dr. Ignaz Semmelweis (1818-1865) first proposed hand washing
Dr. Joseph Lister (1827-1912) introduced disinfection techniques to reduce microbes in medical settings
Sugar alcohol vinegar
Fruit wine
Yeast bacteria
fermentation
Fleming 1928
Antibiotics
Penicillium mold
Nobel Prize 1945 fro penicillin
Autotrophs
Autotrophs | Heterotrophs |
Self-feeders | Other feeders |
Photosynthetic microbes | Decomposing microbes |
CO2 as carbon source | Organic carbon source |
Environment bacteria , protist, fungi |
|
Don't cause disease | Cause infection |
Symbiosis: normal flora live in peace with us and same time benefit us .
Parasite: benefit from the host (don't kill the host)
Microbial Nutrition
Nacronutrients
Organic compound required in large amount composed of
Proteins, carbohydrates, lipids
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphate
Sulfur
Micronutrients or Trace Elements
Elements and gases required in small amounts. Inorganic, metals (iron, manganese, zinc, nickels), and Gases CO2, O2, N2.
Water composes the remaining 70% of cytoplasm. More water more opportunity to growth.
Catalyst
H2O
Peroxide
Energy Production in Heterotrophs
Fermentation
Sugar ----> acid or alcoholic/ CO2 + ATP (small amount) NOTE: slow process, no O2 required
Aerobic Respiration
Sugar + Oxygen -----> ATP + CO2 + H2O
Anaerobic Respiration
Sugar + nitrate (NO3-) ----> ATP + nitrite NO2+
Sugar + sulfate (SO42-)----->ATP + hydrogen sulfate (H2S)
Temperature Requirements
Psychrophile: microorganism is capable to growth at 0o C optimum temperature is 15oC
Mesophile: organism that growth at intermediate temperature
Thermophile: organism growth at temperature greater than 45oC
pH Requirement
Acidophile: organism that live in pH 1-5
Neutrophile: organism that live in pH 5-9
Alkaliphile: organism that live in pH 8-12
Oxygen Requirement
Facultative Anaerobe: prefer oxygen if available. If not change to fermentation.
Microaerophile: prefer small amount of O2. It is present in mucous membrane
Capnohile: prefer CO2 concentration. It's presented in lungs
Aero tolerant Anaerobe: don't utilize O2
Obligate Anaerobe: organism that don't tolerate O2
Obligate Aerobe: need O2
H2O + O 2
Kill anaerobic bacteria
http://academic.pgcc.edu/~kroberts/Lecture/Chapter%206/06-03_O2Requirements_L.jpg
Osmotic Pressure in Bacteria
Hypertonic Solution: water follows out of cell membrane collapse but wall remains=plasmolysis
Hypotonic Solution: water goes inside the cell until cell explode. Gram negative
Isotonic Solution: water flows equally
NOTE:
Salt is important in water movement
Halophile: salt loving
Osmophile: hypertonic loving (diabetes)
Bacillus: survive hot temperature and form spores produce anthrax
Passive Transportation
Base on concentration
Water and salt go on different directions
No energy needed, moving with concentration high to low
Simply diffusion (O2 CO2) pass across bilayer
Facilitated diffusion (sugar, ions) no energy required, use protein channels
Osmosis (water) where is salt, water follows
Active Transport Across Membrane
Energy needs
Going against concentration
Group translocation the sugar goes in and attach to a phosphate (it's to big to go out). How bacteria repairs themselves and how they retain sugar.
Endocytosis and exocytose eukaryotes only
Binary Fission
A sexual reproduction
Chromosome replicates
Cytoplasm divides
Daughters cell are identical to each other and to former parent cell
Typical Growth
Lag phase | Adjustment |
Exponential phase | Very quick growth you have symptoms |
Stationary phase | No increase in number |
Death (decline) phase | As rapid as exponential phase. You need your white cells and antibiotics |
Quorum Sensing
When the bacteria sense that there are more around. They start to produce the toxin to kill the other cell. However that toxin only damage US.
Chapter 1: The Main Themes of Microbiology
Microbiology: is the study of organisms too small to be seem without magnification .
Microorganisms includes:
- bacteria
- viruses
- fungi
- protozoa
- algae
- helminthes (worms)
What benefits do Microbes Provide?
Ecological Roles:
Photosynthesis | Bacteria/algae |
Decomposition | Fungus/bacteria |
Nitrogen fixation | Bacteria |
Bioremediation |
|
Commercial Products:
- Cheese, yogurt, alcohol, bread, mushrooms
- Antibiotics, produce by living organism to kill other bacterias
- Make up, detergent, paint
Health Roles:
Normal Flora (microbiola), protects us from opportunistic bacteria
Vitamin K E. coli
digestion
Note: the bacteria take the Nitrogen from the atmosphere that why we get N into our body
Example: If there are an oil spill in the ocean scientist put micros that can eat oil to clean up oceans
Characteristics of Microbes
Prokaryotes:
- Bacteria and Achaea (extreme bacteria) live in extreme environment as volcano
- Single cell or unicellular lack of nuclei and organelles
Have DNA (chromosome) but it's not package in the nucleus
Eukaryotes:
- Protozoa, Algae, Fungi
- Multicellular have nuclei and organelle
- Chromosome are inside the nuclei
Viruses:
- Acellullar, parasitic particles (non living)
- Composed of nuclei acid and protein
- No cell structure
- Have to be in a host cell to reproduce
There are two types | Virus that infect you |
| Virus that infect bacteria |
Microbial Dimensions
Bacteria are measured in micrometers = um (0.2 to 100 um)
Virus are measured in nanometers =nm (10- 100 nm)
Taxonomy and nomenclature
- Carl von Linne (Linnaeus, 1700's) plant or animal
- Taxonomic hierarchy based on similar traits:
- Kingdom Family
- Phylum Genus
- Class Species
- Order
- Kingdom Family
- Binomial nomenclature: genus + species
Genus and species italicized/ underlined
Species only can be abbreviated after first use:
Genus | Species |
Escherichia | coli |
Emtanoeba | coli |
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