Lecture Notes: Introduction to Microbiology and History

Overview

• Focus on microbiology history starting from 400 years ago
• Transition from the idea of spontaneous generation (abiogenesis) to biogenesis

Key Historical Figures and Experiments

Francisco Redi

• Lived around 400 years ago
• Tried to disprove spontaneous generation
• Experiment:
  • Used three flasks with meat:
    • One unsealed
    • One sealed
    • One covered with gauze
  • Result: Maggots appeared only in the unsealed flask, showing that flies, not meat, were responsible for maggots.

Louis Pasteur

• Known as the "father of microbiology"
• Contributed To:
  • Disproving abiogenesis
  • Developed a swan-neck flask experiment to show microorganisms in the air caused growth in media
  • Introduced aseptic techniques and pasteurization

Anton van Leeuwenhoek

• Developed early microscopes around the 1660s
• Observed microorganisms, termed "animalcules"
• Microscopes achieved up to 300x magnification

Joseph Lister

• Pioneered aseptic techniques in surgery
• Emphasized sterilization of surgical tools and handwashing

Holmes and Semmelweis

• Advocated for handwashing to reduce childbirth-related mortality in hospitals

Robert Koch

• Developed Koch's postulates linking specific microorganisms to diseases
• Contributed to the germ theory of disease

Microbiology Fundamentals

Germ Theory of Disease

• Germs cause disease
• Widely accepted principle

Cellular Organization

• Eukaryotes:
  • Have membrane-bound organelles (mitochondria, ER, nucleus, etc.)
  • Can be multicellular
• Prokaryotes:
  • Lack membrane-bound structures
  • Always unicellular (e.g., bacteria, archaeans)
  • Smaller than eukaryotes

Viruses

• Unique category
• Not independent living organisms
• Composed of hereditary material (DNA/RNA) and protein coat
• Function as "host hijackers"

Conclusion

• This concludes Chapter 1
• Future chapters will delve deeper into cellular structures and different types of organisms