Microbio- scope and history of microbiology

why are microbes important

• Help maintain the ecological balance on Earth

• Commercial applications to synthesize chemical products

• Important in the food industry

• Live in (and on) humans and other animals to maintain the animal’s health Infectious diseases

Ecological balance: photosynthesis

Light-fueled conversion of CO2 to O2

~50% of photosynthesis is carried out by microorganisms (algae)

ecological balance: decomposition

breakdown of dead matter and wastes to simple compounds

ecological balance: greenhouse gases

gases that impact Earth’s temperature

• Some produced by environmental microbes and microbes living in the gastrointestinal tract of animals

biotechnology

Industrial production of products using genetically manipulated microorganisms

examples of biotechnology

• Biofuel production from algae

• Bioremediation using Shewanella to detoxify radioactive waste

• Production of human insulin using genetically engineered E. coli

• Antibiotic production

how many human cells per person

10^13 (84% RBC

how many bacterial cells per person

10^13- 10^14

what does microbiota include

Bacteria (Bacteriome)

Archaea (Archaeome)

Viruses (Virome)

Bacteriophage (Phageome)

Protists, Fungi & Helminths (Eukaryome)

Fungi (Mycobiome)

Robert Hooke (1665)

• created cell theory

• discovered cell

• Used improved microscope and observed “cells” in cork tissue

• saw compartments and called them cells

Antoni van Leeuwenhoek (1673-1723

Viewed “animalcules” in rainwater and materials scraped from his teeth

• used a microscope and looked at things he could not see with naked eye

• kinda discovered microbes but called them something different

spontaneous generation

The belief that life arises from dead material

• many scientist set out to disprove this idea

Francisco Redi 1668

experimented sealed vs nonsealed jar soiling food

• when no air was getting in no maggot when air got in maggots.

what was the problem with Francisco Redi jar experiments with spoiled vs non spoiled food

Antagonists were still convinced that “animalcules” could still generate from nonliving material

• (even though large organisms (maggots) were now not believed to come from spontaneous generation)

Lazzaro Spallanzani 1765

Carried out experiments to test the hypothesis of the spontaneous generation of life.

what experiment did lazzaro spallanzani do

Showed that boiling broth solutions and sealing flasks would prevent growth of microbes

• this helped refute spontaneous generation

what was the problem with spallanzani’s experiment

that sealed flask prevented air from entering the flask

Rudolf Virchow 1858

came with theory of biogenesis

• life arises from life

• issue of spontaneous generation still unresolved

Louis Pasteur 1861

repeated Spallanzani's experiment with swan neck flasks

what did pasteur experiment show

• Microbes are present on nonliving matter

• Microbes can be destroyed by heat

• Airborne contamination can be obstructed, and air itself does not create microbes

what did the discoverys from pasteurs experiment become the basis of

aseotic technique

Fracastoro 1546

germ theory first proposed

• Microorganisms are the causative agent for disease

• for centuries this theory was not accepted because we didnt know what caused diseases

when was the golden age of microbiology

from 1857-1914

golden age of microbiology

Had rapid advances in field that led to establishment of microbiology as a science

• during this golden age it strengthened the germ theory

Ignaz Semmelweis 1840s

• was a surgeon and at the time doctors would work on dead bodys then go straight to giving birth to children

• realized the reason there was so many cases of childbed fever was because they were not washing there hands

• he started to wash hands with chlorinated lime solutions and the cases of childbed fevers dropped

• but he didnt get the credit he deserved til later

who is the father of modern surgery

joseph lister 1860s

what did joseph lister do

he applied phenol on wounds to reduce infection

• phenol was toxic so helped reduce infection in wounds

Robert Koch 1876

first to show that bacteria actually caused disease

what were robert koch postulates

1. Same pathogen present in every case of disease

2. Pathogen isolated from diseased host and grown in pure culture

3. Pathogen from pure culture must cause disease when inoculated into healthy animal

4. Pathogen is isolated from inoculated animal is shown to be the original organism

Angelina Hesse

Worked as an assistant preparing bacterial growth media with her husband Walther Hesse for Robert Koch.

what did angelina hesse discover/ determine

Determined that agar could be used to prepare solid media, allowing for the isolation of bacteria in pure culture.

• Agar maintains its gel-like properties at warm temperatures and is not consumed by bacteria. which allowed Koch to isolate Mycobacterium tuberculosis, the causative agent of tuberculosis.

edward jenner 1796

developed the vaccine for smallpox

how did jenner create the vaccine

• discovered that ppl who worked with cows didnt get small pox just cowpox which is a milder diease so he infected a boy with cowpox them smallpox and he did not get small pox

chemotherapy

Treatment of a disease with chemicals

how does chemotherapy work

Chemical has to be more toxic to the bacteria but less toxic than the host (human) can handle

paul ehrlich 1910

Discovered salvarsan, an arsenic derivative for treatment of syphilis

salvarsan

the first chemotherapeutic drug against bacterial infections.

Alexander Flemming 1929

discovered penicillin (first antibiotic)

what are antibodies

chemicals produced naturally by bacteria and fungi and work against other microorganisms

when was penicillin mass produced

1940’s

what are problems withantibiotics

• antibiotic resistance

• allergies