Microbiology Unit 1: Introduction

1. Microbiology and Parasitology
UNIT 1: INTRODUCTION

2. Some rules
• Listen when others are talking
• Show respect for other opinions
• If you don’t understand, don’t hesitate to ask (raise hand)
• No cellphones in the class room
• Full participation is asked

3. Microbiology
Virus: Ebola
Fungi: Mushroom
Bacteria: Salmonella
ENEMY OR… …FRIEND
Algae: Algal bloom
MICROBES

4. Course content
• Theory
– Burton’s Microbiology for the Health Sciences – P.G. Engelkirk & J. Duben
– Microbiology and Infection – T.J.J. Inglis
• Practice: demonstrations in laboratory science
– Growth of bacteria
– Growth of fungi
• Tests
• Assignments
• Final examination

5. Website
• http://pson-biochemphys.yurls.net/en/page/

6. Today
• Microbes
– Definition
– Presence
– Variety
– Enemy or friend?
• Historical Background
– Earliest known diseases
– Fouding fathers
• Microbiology in health care
– Possible careers

7. Definition?
• MICRO – BIO – LOGY
– μικρος = micros = “small”
– βιος = bios = “life”
– λογος = logos = “science”
– “The study of very small living organisms”
• or: MICROBIOLOGY
– “The study of microorganisms (microbes) usually less then 1 mm in
diameter which requires some sort of magnification to be seen clearly”
Burton’s Microbiology: Chapter 1

8. Presence of Microbes
• Microbes are ubiquitous: virtually everywhere
– Water (photosynthetic algae, plankton)
– Dead or decaying materials (decomposers/saprophytes)
– Soil (bacteria used in microbial ecology)
– Animals/plants (bacteria and protozoa in intestinal tract)
– Food/drinks (yeast in bread and beer)
– Laboratory (study or to produce antibiotics, insulin, hormones)
Burton’s Microbiology: Chapter 1
MANY
MICROBES
ARE
USEFUL
(FRIENDLY)

9. Variety of Microbes
• Categories
– Acellar: Viroids, Virus, Prion
– Prokaryotes (cellular without nucleus): Bacteria, Archaea, Cyanobacteria
– Eukaryotes (cellular with nucleus): Algae, Fungi, Protozoa
Burton’s Microbiology: Chapter 1
Microbes
Acellular
Viroids
Prions
Virusus
Cellular
Prokaryotes
Archaea
Bacteria
Cyanobacteria
Eukaryotes
Algae
Fungi
Protozoa

10. Microflora
Indigenous
microflora
(100 trillion)
Nonpathogens
(97%)
Opportunistic
pathogens
Pathogens /
infectious agents
(3%)
FRIENDS
MICROBIAL ALLIES
ENEMIES
MICROBIAL ENEMIES
“GERMS”
USED-TO-BE-FRIENDS
POTENTIAL ENEMIES
Burton’s Microbiology: Chapter 1
• All microbes living on our bodies: Indigenous Microflora

11. Disease
• Microbial enemies…
– …cause disease
– “Pathogens”
– Two categories
• Infectious diseases
– 50.000 deaths/day
– Majority in
developing countries
• Be aware of…
– Infectious diseases
– Pathogens
– Source
– Transmission
– Protection/prevention
Burton’s Microbiology: Chapter 1

12. Earliest known diseases
3180 BC
1900 BC
1500 BC
1122 BC
790-640 BC
430 BC 1493
0 2015
Egypt:
First recorded pestilence
Troy:
Bubonic plague
Egypt:
Epidemic fevers
China:
Smallpox
Rome:
Epidemics of plague
Greece:
Epidemics of plague
Europe:
Syphilis
Burton’s Microbiology: Chapter 1

13. Historical background
• Once upon a time…
Burton’s Microbiology: Chapter 1
… they had no idea

14. Antoni van Leeuwenhoek
• Dutch merchant
• Godfather of Microbiology
– First to see live bacteria
– Quote from Microbe Hunters
• Inventor microscope (hobby)
– Examined water, blood, sperm,
teeth, stool, etc.
– Observed tiny living creatures:
“ANIMALCULES”
• No scientist
– No speculation on origin
– No association with disease
Burton’s Microbiology: Chapter 1

15. Leeuwenhoek’s microscopes
• Simple or single-lens microscope
– One magnifying lens
– Magnifying power of x 300
– Tiny glass lens mounted in a plate
– Specimen placed on small pin
– Screws used to adjust position
Burton’s Microbiology: Chapter 2
Drawings of van Leeuwenhoek

16. Robert Koch
• German Physician
– Germ theory of disease: “specific
microbes cause specific disease”
– Developed fixing, staining,
photographing bacteria
– Contributed to TB skin test
– Cultivate bacteria on solid agar
• obtain pure culture (one type)
• Developed Koch’s postulates
– Experimental procedure
– Proof germ theory of disease: “specific
microbes cause specific disease”
– e.g. Antrax bacillus  Antrax
Burton’s Microbiology: Chapter 1

17. Koch’s Postulates
After fulfilling Koch’s Postulates: prove that microbe is cause of particular disease
Burton’s Microbiology: Chapter 1

18. Edward Jenner
• British physician and scientist
• 1976: Developed smallpox vaccine
– Hypothesis:
“Having cowpox protects from
smallpox”
– Vaccin: sample from milder cowpox
– First to publish results of vaccination
– Origin of immunology?
Burton’s Microbiology: Chapter 16

19. Louis Pasteur
• French Chemist
– Fermentation process
– Disproved abiogenesis
(sponteneous generation)
– Aerobes/Anaerobes
– Developed Pasteurization
– Germ theory of disease: “specific
microbes cause specific disease”
– Championed changes in hosptial
practices: minimize spread disease
– Vaccins for chicken cholora, antrax
and rabies.
• Research center for
infectious disease
Burton’s Microbiology: Chapter 1

20. Joseph Lister
• British surgeon
– Asepsis (without infection)
– Antisepsis (against infection)
• “Phenol as antiseptic”
– Apply to wounds, hands, instruments,
wound dressings
– Perform surgery in phenol mist (irritating)
• Use of sterile equipment
• ↓ wound infections/mortality
• First pure culture (in liquid medium)
Burton’s Microbiology: Chapter 8,12

21. Alexander Fleming
• Scottish bacteriologist
• First antibiotic
– Accident: mould (fungi) on bacteria
culture plate
– Antibiotic (Penicillin) produced by
mould inhibited growth of bacteria!
• WWII: Penicillin saved thousands of lifes
Burton’s Microbiology: Chapter 9

22. Ronald Ross
• British medical doctor (born in India)
– Discovered malarial parasite in
mosquito
– Realization: “Malaria transmitted by
mosquitos”

23. Ignaz Semmelweis
• Hungarian physician
• The Father of Handwashing
– Many women died from puerperal fever
(childbed fever)
– Physicians directly from autopsy room
to delivery clinic
– Spread by hands of physicians/students
– Rule: “wash hands with antiseptics”
– ↓ Maternal mortality rate
Burton’s Microbiology: Chapter 12

24. Career in Health Care
• Bacteriologist (Bacteria)
• Phycologist (Algae)
• Protozoologist (Protozoa)
• Mycologyst (Fungi)
• Virologist (Viruses)
• Pursue career in
medical microbiology?
– Study pathogens, infectious diseases
and body’s defense mechanisms
– Development of vaccines
– Epidemiology (public health)
– Immunology (immune system)
– Clinical/diagnostic microbiology
(laboratory diagnosis)
Burton’s Microbiology: Chapter 1

25. The End