Introduction to Microbiology

• Microbiology is the study of microorganisms which must be viewed with the aid of a microscope or electron microscope. 


• The importance of microbiology includes: used in biomedical research, creation of medicines, environmental applications and new research tools.


• Disease causing organisms include: protists, bacteria, viruses and other microorganisms.

• Bacteria are important for fixing N2 in a usable form for plants. 


• Bacteria and some fungi are important in decomposition and recycling of raw materials.


• Industry applications of microbiology: waste management, food industry, mining, medicine, research and biotechnology.


• 1660�s Robert Hooke observed microorganisms for the first time with a microscope and coined the term �cell�.


• 1632-1723 Anton van Leeuwenhoek credited with having observed the first bacteria.


• 1828-1898 Ferdinand Cohn developed the first classification scheme based on bacteria shape.  Cohn detailed and described the life cycle of Bacillus.
  Cohn�s Classification System:
  • Sphaerobacteria are spherically shaped.
  
  
  • Microbacteria are rod shaped
  
  
  • Desmobacteria are filamentous
  
  
  • Spirobacteria are spiral shaped
  
  


• 1822-1895 Louis Pasteur Defined pasteurization to prevent spoilage of food by bacteria, develop vaccines and disproved the scientific dogma of �Spontaneous Generation�.  He defined �Germ Theory� and demonstrated that germs were responsible for disease.


• 1843-1910 Robert Koch identified anthrax and developed agar growth medium.  Koch�s postulates was a systematic method to establish the microbial cause of disease.


• Ignaz Semmelweis was the first to recognize the need for good hygiene during medical procedures.  The first to identify nosocomial infections.


• 1827-1912 Joseph Lister developed antiseptic methods for use in surgery and medicine.


• 1854-1915 Paul Ehrlich developed chemotherapy to cure infectious diseases and discovers antibiotics to treat sleeping sickness and syphilis.


• 1881-1951 Alexander Fleming discovered penicillin and lysozyme.


• 1864-1920 Dmitri Ivansvski discovered the first virus which is known as the tobacco mosaic virus (TMV).


• 1952 Hershey & Chase Experiments identified that DNA was the genetic material of bacteriophages.


• Hershey Case Experiment: using phage radioactively labeled with P32 (DNA) or S35 (protein) they infected bacteria cells.  They found the P32 inside the bacteria not S35. 

Recommendations for Success in Microbiology

• Successful completions of general biology 2 semesters


• Knowledge of basic chemistry and biochemistry


• Basic understanding of classification


• Review layout of text book used in the course.


• Read and master learning objectives laid out in the text book.


• Master definitions presented in the course.