Foundations of Microbiology and Microbes

Aug 13, 2024

Introduction to Microbiology

Overview

  • Microbiology studies microorganisms (microbes) which are too small to be seen without a microscope.
  • Microbes are ubiquitous, found in diverse environments including oceans, soil, air, and on skin.
  • Misconception that microbes are harmful; most are harmless and beneficial, e.g., in fermentation and oxygen production.

Historical Figures in Microbiology

  • Hippocrates: Dismissed supernatural causes for diseases.
  • Vet Morrow: Suggested invisible entities could cause disease.
  • Antonie van Leeuwenhoek: "Father of Microbiology," first to observe microbes using a magnifying lens (not modern microscopes).
  • Robert Hooke: Invented the microscope, discovered cell theory by studying cork cells.
  • Louis Pasteur: Discovered fermentation, pasteurization; showed that microbes in the air cause spoilage; developed early vaccines.
  • Robert Koch: Developed Koch's Postulates, proving specific microbes cause specific diseases (e.g., anthrax by Bacillus anthracis).

Classification of Microorganisms

  • Three Domains of Life:
    • Bacteria: Most common microbes studied.
    • Archaea: Unique, odd microbes.
    • Eukarya: Includes microbes, plants, animals, and humans.
  • Binomial Nomenclature:
    • Scientific naming using genus and species (e.g., Staphylococcus aureus).
    • Genus capitalized, species lowercase, both italicized or underlined.

Microbial Sizes

  • Comparison of size:
    • Animal/plant cells > red blood cells > mitochondria > bacteria > viruses.
  • Viruses are non-living microbes.

Types of Microorganisms

  1. Algae

    • Uni/multicellular, cellulose cell walls, photosynthetic, oxygen producers.
    • Used in food and lab settings.

  2. Protozoa

    • Uni/multicellular, motile, classified by locomotion.
    • Some are parasitic, others harmless in drinking water.

  3. Fungi

    • Uni/multicellular, includes yeasts and molds, chitin cell walls.
    • Mostly harmless, some pathogenic.

  4. Helminths

    • Parasitic worms, included due to microscopic transmission stages.

  5. Viruses

    • Non-cellular, obligate intracellular parasites.

Conclusion

  • Chapter 1 provides a foundational overview of different types of microbes.
  • Focus on bacteria, as these lack membrane-bound organelles, progressing to eukaryotic microbes.