Etiology Chapter 1
John Snow
(1813-1858) -Determined the mode of cholera transmission in London
Florence Nightingale
(1820-1910)- Nurse who implimented cleanliness and other antiseptic techniques during the Crimean War -Went on to found the Nightingale School for Nurses
Prokaryotes
-Bacteria and Archaea -Unicellular and lack nuclei -Reproduces asexually (make clones)
Biochemistry
-Field sparked by Buchner -The study of metabolism
Buchner's Experiments
-Showed that fermentation does not require living cells -Demonstrated the presence of enzymes
The Classical Golden Age of Microbiology
1854-1914
Miasma (pollution)
Considered a poisonous vapor that caused cholera and other diseases
Disease
Disrupting homoestasis
Redi's Experiment
Found that if flies were prevented from landing on meat, it did not produce maggots
Soho, London
In 1854 it was the hot spot for Cholera (Broad Street)
In 1859
Louis Pasteur discredited the idea of spontaneous generation
Postulate 3
Microorganisms from the pure culture are inoculated into a healthy, susceptible animal. The disease is reproduced.
Epidemic
More than the expected number of cases at that particular time
Algae
Multicellular photosynthetic organisms
Molds
Typically multicellular organisms that grow as long filaments
Bioremediation
Use of living bacteria, fungi, and algae to detoxifying polluted enviroments
Fungal Pathogens
ex. Cryptococcus neoformans -AIDS patient
Bacterial Pathogens
ex. Escherichia coli or Entamoeba coli - 1-3 micrometer
Linus Pauling
proposed in 1965 that gene sequences could provide a means of understanding evolutionary relationships and processes, establishing taxonomic categories that more closely reflect these relationships, and identifying the existence of microbes that have never been cultured
Antoni van Leeuwenkhoek
-Began making and using simple microscope -Often made a new microscope for each specimen -Examined water and visualized tiny animals, fungi, algae, and single-celled protozoa: "animalcules"
Problems with the postulates
-Can be infected and not show symptoms (have pathogen, but no disease) -Mutations -Ethics -Cause could be 2+ organisms
Ignaz Semmelweis
-Determined the source of blood poisoning of women in childbirth (Puerperal Fever) -Handwashing
Joseph Lister
-Developed the practice of antisepsis chemical disinfection of external living surfaces -Spraying and surgical incisions wounds with phenol
Robert Koch
-Formalized standards to identify germs with infectious diseases -Postulates became the standard for linking a specific organism to a specific disease
Eukaryotes
-Fungi, Protozoa, Multicellular organisms -Have a nucleus -Membrane-bound organelles
Immunology
-Jenner began the field of immunology -The study of the body's specific defenses against pathogens
Louis Pasteur
-Proposes that germs cause infectious disease -Pasteurization -Proposed germ theory in 1862 -Experiment involved swan neck flask
Pathogen
A biological agent that causes disease or illness in its host
Gene Therapy
A process that involves inserting a missing gene or repairing a defective one in human cells
Taxonomic system
A system for naming plants and animals and grouping similar organisms together
Yeast
Are unicellular and typically oval to round
Cholera
Bacteria (Vibro cholerae)
Redi's Experiment
Found that if flies were prevented from landing on meat, it did not produce maggots -Scientist began to doubt Aristotle's theory
Gram-negative cell
Generally, a prokaryotic cell having a wall composed of a thin layer of wall material, an external membrane, and a periplasmic space between; appears pink after the Gram staining procedures
Germ Theory of Disease
In 1857 that microorganisms are also responsible for disease
Spontaneous Generation
In the 1600's many people thought life generated spontaneously from putrid and decaying materials
Variolation
Involved exposing individuals to dried smallpox specimens
Recombinant DNA Technology
Is DNA composed of genes from more than one organism
Gram-positive cell
Prokaryotic cell having a thick wall; in bacteria, composed of a thick layer of peptidoglycan containing teichoic acids; Gram-positive cells retain the cyrstal violet dye used in the Gram staining procedure, appearing purple
Metabolism
Refers to the sum of all chemical reactions within an organism
Pure Culture
Robert Koch- by adding gelatin to his broth RK was able to grow bacterial colonies in a Petri dish
Infection Control and Epidemiology
Snow's study was the foundation for two branches of microbiology
Needham's Experiments
Stated that there must be a "life force" because he heatedthe vials to kill everything, but yet they were still cloudy
Ehrlich's Experiments
Suggested that chemicals could be used to kill microorganisms deferentially
Gram Stain
Technique for staining microbial samples by applying a series of dyes that leave some microbes purple and other pink (Developed by Christian Gram in 1884)
Postulate 4
The identical microorganisms are isolated and recultivated from the tissue specimens of the experimental animal
Postulate 2
The microorganism are isolated from the tissues of a dead animal, and a pure culture is prepared
Postulate 1
The same microorganism are present in every case of the disease
Etiology
The study of causation or origination of a disease or medical condition
Genome
The total genetic information of an organism
Protozoan Pathogens
ex. Leishmania -proto "first" & zoan "animal" -single cell organism
Multicellular Pathogens
ex. Liver fluke, ascaris and hookworms
Viral Pathogens
ex. West Nile Virus -40-60 nanometers
Molecular Biology
Combines aspects of biochemistry, cell biology, and genetics to explain cell function at the molecular level
Spallanzani's Experiment
Contradicted Needham's experiments. His flask stayed clear after being heated for an hour...he concluded 3 things -Needham failed to heat his vials sufficiently -Microorganisms exist in the air -Spontaneous generation is false
Edward Jenner
Developed vaccination, inoculating individuals with cowpox
Carl Woese
Discovered that significant differents in nucleic acid sequence among organisms clearly reveal the cells belong to one of three major groups: bacteria, archaea or eukaryotes
Chemotherapy
Ehrlich's discoveries began the branch of medical microbiology