Intro to Mbio

3 types of microorganisms

prokaryotes, eukaryotes, acellular microbe

example of prokaryotes

bacteria & archaea

example of eukaryote

protozoa & fungi

example of acellular microbe

virus

prokaryote

* Lack a membrane bound nucleus
* Single circular chromosome

archaea

live in extreme conditions (high salt concentrations, high temperatures and acidic environments)

eukaryotes

* membrane bound \\n nucleus and membrane bound organelles

virus

acellular requiring a living host cell to reproduce

1665: Robert Hooke

dsicovered cell theory (all living things are composed of cells)

1684: Anthoni van Leeuwenhoek

used microscope to view live microbes which he called ‘animalcules’

Spontaneous Generation

bacteria arise from non-living matter

Biogenesis

arises only from pre-existing living matter

1864: Louis Pasteur

* aseptic technique using a **swan neck flask**
* microorganisms responsible for spoilage from the air and not from spontaneous generation

fermentation

yeast converts sugar to alcohol in the **absence of air**

who discovered fermenation

Pastuer

Pasteurization

**using heat** to kill all present bacteria and prevent spoilage

1881: Robert Koch

**Germ Theory of Disease**: specific microbe is responsible for a specific disease

1798: Edward Jenner

* **developed the small pox vaccine**
* injected a young boy
* infected with cow pox were immune to small pox

1908: Paul Ehrlich

* developed the idea of selective toxicity
* discovered effective anti-microbial **Salvarsan** to cure syphilis without damaging host cells

Selective Toxicity

kill or inhibit the growth of pathogenic organisms while leaving host unharmed

1929: Alexander Fleming

discovered mold of Penicillium chrysogenum can inhibit the growth of bacteria on plates contaminated with the mold