WEEK 2

BMY3101-1 MICROBIOLOGY I

WHAT HAVE I LEARN?

The class start with one hour of explanation and discussion on how to submit our mind map, all the details on how to do and where to submit the E-portfolio. Now I am very clear about what to do before and after every lessons. After a five mins break and finally we start our class - into the microbes world. A lot things have been added into the brain.

GENERAL CHARACTERISTIC OF ARCHEA

• Prokaryotes
• Cell wall lack of peptidoglycan 
• Extremophiles
  Which means the archaea can survive under extreme environment for example the hydrothemal vants ( valcano underneath ocean which about 400 degree Celsius )
• Chemotrophic
  Chemotrophs are organisms that obtain energy by the oxidation of electron donors in their environments. 
• Chemolitotrophics
  Chemolithotrophs obtain their energy from reactions with inorganic salts
• Halophiles 
  Which means the archaea need high concentration of salt ( NaCl) to survive 
• Thermoacidophiles
  Which means high acidity and high temperature for example in the hot spring 

GENERAL CHARACTERISTIC OF FUNGI

• Eukaryotes 
• Multicellular fungi : mushroom
  Unicellular fungi : yeast
• Cell wall is made up of chitin ( which can be found on insects )
• most are molds (form masses of mycelia from hyphae )
  One of the molds is mucor  which commonly found in soil, digestive systems, plant surfaces, some cheeses like tomme de savoie, rotten vegetable matter and iron oxide residue in the biosorption process.
• nutrient absorption from dead materials 
• Saprophytes

Amanita muscaria, commonly known as the fly agaric or fly amanita, is a mushroom and psychoactive basidiomycete fungus, one of many in the genus Amanita. They are very poisonous.

GENERAL CHARACTERISTIC OF PROTOZOA

• Eukaryotes
• Unicellular
• Movement : pseudopods, flagella, or cilia
• Nutrients absorption from environment 
• can be found in the drain

GENERAL CHARACTERISTIC OF ALGAE

• Eukaryotes
• Photosynthetic 
• Unicellular or multicellular 
• Cell wall make up pf cellulose (can be found in plant )
• Examples : Red algae (Rhodophyta ), Brown algae (Heterokontophyta ), Green algae (Chlorophyte )

Algae are used in Wastewater Treatment facilities, reducing the need for greater amounts of toxic chemicals than are already used. Algae can be used to capture fertilizers in runoff from farms. When subsequently harvested, the enriched algae itself can be used as fertilizer.

GENERAL CHARACTERISTIC OF VIRUS

• Acellular - Not cellular 
• Very small, very specific 
• Cannot produce by themselves 
• Can only be seen using fluorescence and electron microscope
• Can have either DNA or RNA only ( two are not possible to be exist at the same time )

Whittaker's 5 kingdom system

Brief History of Microbiology

Antonie van Leeuwenhoek

• first person to create a microscope 
• first to found out microorganisms under microscope 
• single-celled organisms, he referred as "animalcules "

The first observations

• The invention of microscope in 1660s by Robert Hooke

Robert Hooke's microscope. Perhaps his most famous observations were in his study of thin slices of cork, describing the pores, or "cells" he viewed. Hooke had discovered plant cells, or more precisely, Hooke had been viewing the cell walls in cork tissue.

• Discover of van Leeuwenhoek led to interest of the scientific community of the time in origins of there tiny living things.
  Proposed SPONTANEOUS GENERATION : Life arise spontaneous from nonliving matter

Evidence to spontaneous generation

• John Needham
  Heated nutrient fluids ( chicken and corn broths) before pouring covered flasks were teeming with organisms when cooled
  Microbes still found, why?
  - Flasks were not sterilize
  - Flasks were not covered tightly 
• Lazzaro Spallanzani
  -dissapproved Needham's theory
  -Nutrient fluids heated after being scaled in a flask did not develop microbial growth
  - Spallanzani's work was cristicised on the grounds that there was not enough oxygen in the sealed flasks to support microbial life.

Pasteur's experiment to disprove theory of spontaneous generation

• Filled several short-necked flasks with beef broth, bolied the contents
• Some flask are sealed, some left open
• sealed after boiling : no microorganisms.

Rudolf Virchow 

challenge theory of spontaneous, use concept of biogenesis
Biogenesis : Living cells can arise only from preexisting living cells 

( Spontaneous generation VS biogenesis issue was resolved by Louis Pasteur in 1861

• Placed broth in open-ended long necked flasks bent into S- shaped curve
• Boiled the contents on the flasks and cooled, unsealed 
• No signs of life

Conclusion:

- Air passed through but curved neck trapped airborne microorganisms

- Microbial life can be present in everywhere and can be destroy by heat

- Methods can be devised to block the access of airborne microorganisms to         nutrient environments

* Basic of aseptic technique

The germ theory of disease

• Proven by Robert Koch in 1876
• Discovered Bacillus anthracis in blood cattle that died of anthrax 
• He cultured the bacteria and inject into healthy animals, the animals results in sick and died, bacteria is reisolate from the died animals, its the same with the inoculated ones
• Koch's postulates

Koch's postulates 

• Same pathogen must be present in every case of disease
• Pathogen must be isolated from the diseased host and grown in pure culture.
• Pathogen from pure culture must cause the disease when inoculated into healthy laboratory animals
• Pathogen must be isolated from the inoculated animal and must be shown to be the original organism 

Exception  to Koch's Postulates

1. Some microorganisms could not be cultured in artificial media 
2. Disease caused by different species of microorganisms could elicit similar symptoms.
3.  Some pathogen can cause several disease conditions.
   For example diarrhea,
   can be cause by E.coli, Salmonella, Botulism ( food poisoning from can food )

Vaccination

• Edward Jenner thought
  - Swinepox
  - Smallpox
  - Chicken pocx
  are related
• Inoculated own son
• Coined " Vaccination " and was adopted by Pasteur to represent the immunization of an individual against a particular disease