Monday, August 25, 2008

Chapter 4: An Introduction to Cells and Prokaryotic Cell Structure and Function


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

 
 

  1. Archaea
  2. Eubacteria
  3. 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
*all bacteria follow this phases the only variable is the time

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:

 
 

  1. Cheese, yogurt, alcohol, bread, mushrooms
  2. Antibiotics, produce by living organism to kill other bacterias
  3. 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
  • Binomial nomenclature: genus + species

    Genus and species italicized/ underlined

    Species only can be abbreviated after first use:

Genus

Species

Escherichia

coli

Emtanoeba

coli