microbiology
The study of microbes
What are microbes?
Organisms too small to be viewed by the naked eye.
Why study microbiology?
a. Medical field careers- treating your patients, preventing spread of disease
b. Your own health - doctors & nurses don't know everything
c. Commercial reasons- many drugs & alcohols
d. Travel- vaccines for certain areas of the world
e. Food industry
1.
Nomenclature
Genus & Species
Staphylo
cluster arrangement
Bacteria
cell walls contain peptidoglycan
Types of microbes
1. Bacteria 2. Archaea 3. Eukarya
Archaea
(if present cell walls lack peptidoglycan) Extremes!! Halophiles (salt mines), thermophiles ("old reliable" gyser), etc
Eukarya
o Protists (slime molds, protozoa, algae)
o Fungi (unicellular yeasts, multi-cellular molds, mushrooms)
o Plants (mosses, ferns, conifers, flowering plants)
o Animals (sponges, worms, insects, vertebrates)
Viruses are not
cells
Viruses
They are a kind of informational parasite ("bad news enveloped in protein"). Viruses are classified separately. They consist of DNA or RNA surrounded by a protein coat. Some possess an envelope coating.
Helminths
multi-cellular animal parasites (roundworms, flatworms, etc)
Many microbes live as
single cells or cell clusters. Some are multi-cellular (e.g. filamentous multicells), but not as complex as animals or plants.
Not all microbes are considered
pathogenic (disease causing).
1. Only members of the Kingdom Animalia (and most Plantae) are not considered
microbes
Normal Microbiota (flora)
present on all humans always does no harm to human carriers.
Pathogens
invade the host and result in disease
Benefits of Microbes in Our World:
� Bioremediation � Insect Pest Control � Recycling Vital Elements � Biotechnology & genetic engineering
used microscope to discover life's smallest structural units were little boxes or "cells". Beginning of Cell Theory- all living things composed of cells.
� 1665: Robert Hooke
tried to disprove Spontaneous Generation. He used sealed jars to prove that maggots don't arise spontaneously from decaying meat. Maggots only appeared in open jars after flies laid eggs.
� 1668: Francesco Redi
was first to observe live microbes/animalcules.
� 1673-1723: Antoni van Leeuwenhoek (a merchant)
developed the vaccination process
� 1796: Edward Jenner
proved microbes are in non living matter (air, water, etc) & can contaminate sterile solutions but non living matter itself does not create microbes. Also, proved microbes can be killed by heat.
Louis Pasteur
solved the spoilage of wine & beer through process of pasteurization- killing most of the problematic bacteria through heat. Now used in milk.
Louis Pasteur
developed "Germ Theory of Disease". Koch discovered rod shaped bacteria in cattle killed by anthrax.
� 1876: Robert Koch
tested hundreds of substances to find a chemotherapeutic agent (salvarsan- arsenic derivative against syphilis).
� 1910: Paul Ehrlich
discovered antibiotics by accident.
� 1928: Alexander Fleming
Our World in Constant Fluctuation:
� Disease disappears - polio
� Disease reappears - mumps (people refusing vaccination), pertussis-whooping cough (vaccine does not protect for a lifetime)
� Disease emerges - bovine spongiform encephalitis (BSE or mad cow), invasive group A streptococcus
Causes of Emerging Infectious Diseases:
1. Evolutionary changes in existing organisms
2. Spread of known diseases to new areas or populations
3. Increasing human exposure to infectious agents in areas undergoing ecological change (ex: deforestation)