BIOLOGY 346 Microbes and society
Bacterial Disease examples
Botulism, Campylobacter, staphylococcus, Escherichia Coli (normally good but is infective), salmonella
Head of virus contains
DNA
3 domains of life:
Eukaryote, Prokaryote (bacteria), and Archea (like bacteria)
Viral disease examples
Flu, cold, smallpox, AIDS, measels, mumps. Difficult to treat. Grows in cells of the host.
Edward Jenner 1796
In 1796, (before the germ theory), Edward Jenner did the first clinical trial of vaccination -people had been doing some form of vaccination before Jenner but Jenner did the first public demonstration. He demonstrated that if you vaccinated someone with cowpox (a minor skin disease for humans) that they would protected against smallpox (a more severe disease)
Acetobactor
MAKES VINEGAR. produces carbohydrate and grows in very little oxtgen
PROKARYOTIC CELL: cytoplasmic membrane
Made of phospholipids and proteins. Determines what moves into the cell and out of the cell. Also performs the same function as the mitochondria and chloroplasts found in eukaryotic cells
microbiome
The complete genetic content of all the microorganisms that typically inhabit a particular environment, especially a site on or in the body, such as the skin or the nose
Three things microbiology was trying to uncover during the time of 1880
The spontaneous genera<on of life (life from inanimate objects).* Infectious disease (transmissible forms).* Philosopher's Stone (substance that was said to be able to turn base metals, such as lead, into gold)
what is agar?
a carbohydrate
plant cells are the ___ cells
biggest
Koch
develop principles to determine if bacteria is pathogenic on not
What do microbes help clean up
environmental disasters (such as oil spills, they degrade it with enzymes)
What is the growth of bacteria determined by?
nutrition/ presence of nutrients
DNA is ___
the most improtant molecule in genetic determination
Transcription
transcribing DNA to make mRNA
Ignaz Semmelweis (1847)
"Savior of mothers"-discovered that the incidence of childbed fever could be drastically cut by the use of hand disinfection in maternity wards Some doctors were offended at the suggestion that they should wash their hands. Practice became accepted later after his death and Pasteur confirmed the germ theory.
theory of spontaneous generation: Jan Baptista van Helmont (early 1600s)
"observed" that rats originate from wheat bran and old rags. A 17th century mouse recipe: •1 pair sweaty underwear •several husks of wheat Place sweaty underwear and wheat husks in an open-‐mouthed jar -‐ let sit for 21 days - Accepted by common people -‐ based on their observations of slime that produced toads, and meat that generated worm-‐like maggots
theory of spontaneous generation: Fransesco Redi (1668)
- disputed theory of SG. Set up a series of tests -‐ covered some jars of meat with fine gauze or paper (test cases) to prevent the entry of flies, compared results to jars of meat left exposed (control). Hypothesis: covered meat should not produce maggots. One piece was left in the open air, resulting in maggots. Another jar was covered with fine gauze to prevent flies from entering the jar. No maggots develop on the meat Although Redi's experiment should have put the notion of spontaneous generation to rest, reports of wee animalcules became widespread during the 1700s
Pasteur and his swan neck flasks
-shape of the flask was an important part of the experiment -The life force in the air can enter flask -‐ flask is not sealed. The bend in the flask's neck traps microbes -There's nothing wrong with the broth in the flask- it will support the growth of microbes if microbes are added to it. -The theory of spontaneous generation has been disproved
for what reasons would bacteria NOT grow
-there was no bacteria in the place that was swabbed -wrong medium was used for the bacteria- maybe AGAR was not suitable for this particular bacteria -the bacteria is potentially not developing quickly enough
LIMITATIONS OF KOCHS POSTULATES
1) Corresponding with number one. Microorganisms of the normal flora/ orignal, under specific circumstances, can cause disease in others. Microorganisms would then be found on healthy and sick individuals (EX: ear infections- caused by bacteria present on the skin) 2) corresponds with number two. Some microorganisms can't be grwon as pure culture- we might not have suitable growth media (we dont know what they eat), some microorganisms must exist in partnership with another microorganism. Virsuses cant be cultivated as pure cultures, cells must always be present. 3) corresponds with number three. Some microorganisms cause disease in one species but not in another. Salmonella is pathogenic to humans but not to turtles or chickens
Koch's postulates/ principles
1) the suspected pathogenic organism should be present in all cases of the disease and absent from healthy animals 2) the suspected organism should be grown in a pure culture 3) cells from a pure culture of the suspected organism should cause disease in a healthy animal 4) the organism should be reisolated and shown to be the same as the original
Robert Hooke First description of cells (1665)
1.All organisms* are composed of fundamental units called cells. 2.All organisms are unicellular or multicellular 3.All cells are fundamentally alike with regard to their structure and metabolism 4.Cells arise only from previously existing cells ("life begets life")
how many pathogenic bacteria that affect humans?
1000
The first pure cultures of bacteria first obtained and grown in the ___
1850s (19th cent)
Golden age of microbiology
1876-1902. Human pathogenic bacteria were discovered during this peroid
around what time did microbiology really get going?
1880
Eukaryote
A cell that contains a nucleus and membrane bound organelles- structurally complex and larger than eukaryote ex) plants, yeasts, molds, fungi, animals
Joseph Lister 1865
An early application of the germ theory was Joseph Listers use of carbolic acid as an antiseptic in the treatment of surgical wounds Death rate from infection dropped drastically
Eukaryote
Anything with a relationship to humans --> Any of the single-celled or multicellular organisms whose cell contains a distinct, membrane-bound nucleus.
around the time of 1880 what were people arguing around disease?
At this time, people were beginning to argue that disease was a transmittable agent. Others disbelieved -disease was considered a punishment for sin. Infectious disease was thought of in strange ways -caused by vapours or miasmas. When people came to believe that diseases were caused by germs, it made for a more logical and practical treatment of disease
Fungal disease examples
Athletes foot. Difficult to treat bc Fungi is a Eukaryote (too closely related to humans- can negatively impact humans)
CDC and BCCDC
Centre for disease control- tell you where not to travel
How do you know that something is living? Hallmarks of life
Compartmentalization and metabolism - Cells take up nutrients from the environment, transform them, and release wastes into the environment. The cell is thus an open system. Reproduction (growth)- chemicals from the environment are turned into new cells under the genetic direction of preexisting cells Differentiation- Some cells can form new cell structures such as a spore, usually as a part of a cellular life cycle Communication- cells communicate or interact by means of chemicals that are released or taken up Movement- Some cells are capable of self propulsion Evolution- Cells contain genes and evolve to display new biological properties. Phylogenetic trees show the evolutionary relationship between cells
Dom Perignon (1678)
Credited with discovering (accidentally) champagne. Wine was fermented in a barrel, but fermentation went dormantwiththe cold weather of winter. It resumed in the spring, and the yeast begin a second fermentation. Additional yeast and sugars are added (to produce the bubbles)
What were microbes first associated with?
Disease (BUT they do alot of good as well)
Prokaryote
Do not have a membrane bound nucleus - simpler morphologically ex) bacteria and archea
Binomial bacteria name examples
Escherichia (family) Coli (class) Staphylococcus (family) aureus/ epidermis (class)
Antoni van Leeuwenhoek (1684)
First describe the presence of bacteria in pepper-‐water soltions (and other natural substances). Also described eggs on the wheat grains with his microscope. Opposed the theory of spontaneous generation - which was thought to be the cause of disease - observed animalcules (moved with purpose, were alive)
Robert Koch
First scientist to prove a specific bacterium causes a specific disease (1890). Develop methodology to develop pure cultures of bacteria. Worked with B. anthracis, M. tuberculosis (all on the open counter) -‐ never contracted disease.
How to identify a pathogen: Robert Koch's Principles
If you find it in sick and healthy people, it is probably not a pathogen. If you find it in only sick people it is probably a pathogen. 1) INFECTIOUS ORGANISM FOUND ONLY IN SICK PEOPLE. 2) GIVE THE PATHOGEN TO ANIMALS AND IT MAKES THEM SICK--> you isolate the pathogen from the sick rat to confirm the organism is the cause of sickness
Louis Pasteur (1859)
Pasteur finally thought out the experiment to disprove the theory of spontaneous generation, once and for all
EUKARYOTIC CELLS: cell wall
Plant and algae cells are examples that do have cell walls .Provides mechanical strength to the cytoplasmic membrane.
Transcription
Process of converting DNA to RNA, the DNA is copied by enzymes in the cell
Pathogens: Extracellular
Produce toxins outside the cell. EX) Staphylococcus,
What do you need to have in sufficient supply for bacteria to grow?
Protein (chemically supplies amino acids) metal ions (ex. FE) vitamins sugar need to have chemical interactions between a community
Spallanzanis experiment
Spallanzani boiled broth's for longer periods of time, sealed some flasks by melting the glass, left others open -After 2 days, the open flasks were teaming with microbes, sealed flasks were sterile. This initiated a heated argument between Needham and Spallanzani over sterilization (boiled broth in closed vs opencontainers) as a way of refuting spontaneous generation Needham claimed that Spallanzanis over-‐extensive boiling used to sterilize the containers had killed the vital force or life force. Needham argued that bacteria could not spontaneously generate in the sealed containers because the life force could not get in. In open containers, the life force could be replenished. In the minimally-‐boiled flasks, he felt the boiling was not severe enough to destroy the life force, so bacteria were still able to develop
when did the theory of spontaneous generation continue to and why??
The controversy over spontaneous generation continued into the mid-‐1800s because many felt that air was necessary for life, and Spallanzanis experiment excluded air
theory of spontaneous generation: Aristotle
The idea that life forms arose spontaneously from non-‐living matter. Aristotle wrote that: •flies, worms, etc., arise from decaying matter, •frogs arise from flooded fields.His observations laid the basis for the doctrine of spontaneous generation
Microbiolgy and its history-when did things begin to happen?
Things really started to happen around the 19th century
PROKARYOTIC CELL: nucleoid
This is the region of the cell where the DNA is concentrated. DNA is the genetic blue-‐print of the cell. DNA is transcribed (copied) by RNA polymerase to make mRNA.
Viral coat
Viruses have a coat of viral proteins and a tail that peirces the cell
PROKARYOTIC CELL: cytoplasm
Water filled compartment where the cell does most of its chemical reactions. Filled with building blocks of cellular molecules
PROKARYOTIC CELL: Cell wall
Water moves freely across the membrane. So much water moves in that the cell membrane could rupture -‐ the cell wall adds mechanical strength to the cytoplasmic membrane
Of the five classes if microbes, which two are related closest to humans?
Yeasts and fungi
5 Classes of microbes
Yeasts, Bacteria, Viruses, Fungi, Archea
Does the cell usually die after bacterial infection?
Yes (too much DNA or protein)
viruses have to grow in___
a cell (attacks the cell and makes 100s or 1000s of virus copies per cell)
PROKARYOTIC CELL: somethings that may be on the outside of the cell... capsule
a layer to protect the cell from drying out- some capsule material is used in food industry (Xanthan gum)
PROKARYOTIC CELL: somethings that may be on the outside of the cell... pili
allows transfer of genetic material
PROKARYOTIC CELL: periplasm
between the membrane and the cell wall- it has proteins which help to transport nutrients into the cell
how to bacteria grow?
by dividing into two identical cells- binary fission (A type of asexual reproduction common among prokaryotes wherein a cell divides giving rise to two cells, each having the potential to grow to the size of the original cell.) One cell turns into two.. two into four.. etc
Lichen
combination of fungus and algae and bacteria. It can be poisonous but it purifies the air and reduces pollution. If lichens are growing in a certain area, it means the air is pretty clean
Translation
converts message of RNA and produces proteins
Pasteur
did alot of work on Tuberculosis- great white plague.
Lazzaro Spallanzani (1767)
discredited Needham- said that the heating of his bottle didnt kill everything inside - repeated experiment- and no growth occured BUT SG persisted
Bacillus Subtilis
divides by cell division- can form spores, almost indestructive
How does e coli grow?
divides by cell division- does not form spores. When it runs out of nutrition it is stagnant
Non pathogens
do not cause disease
Pasteur
identified pathogen and was able to grow it seperately from patient -also worked with rabies -inovled in making first vaccine for TB (not successful)
Bacteriophage
infects bacteria
Virus
infects plants, humans
bacteria define the limitis of ____ (in terms of...)
life (In terms of pressure, temperature, humidity, dryness, shortage of oxygen)
bacteria found where:
life exists (E.g. Not in volcanoes)
Pathogens: Intracellular
lives inside a cell. EX) E. Coli, Salmonella
PROKARYOTIC CELL: somethings that may be on the outside of the cell... Flagella
long protein structure- may have one or many- involved in cell movement
Archea
look and act like bacteria but have different properties -DNA analysis -discovery in 1970s
PROKARYOTIC CELL: chromosome
made of DNA, deoxyribonucleic acid: has all of the genitic information the cell needs on how to be a cell- it is a single chromosome and in a circular shape -sometimes there are also plasmids which are also made of DNA and circular- they can contain genetic information that gives the cell a real advantage under some circumstances
It was originally thought that there weren't ___ bacteria
many
Anything fermented means ______ were at work
microbes
do bacteria exist on their own in nature?
no they exist in bacterial communities
more bacteria on earth than any other...
organism
what is the difference between pathogens and non pathogens?
pathogens have more DNA (Genes) than non pathogens
PROKARYOTIC CELL: ribosomes
protein manufacturers for the cell- they recieve orders from DNA by they way of an intermediate called mRNA -They translate the information on mRNA to make protein. -They assemble proteins from amino acids. There are 20 different amino acids that are used to make proteins. The instructions of what order and how many amino acids are needed is provided in the mRNA (messenger RNA)
EUKARYOTIC CELLS: cytoplasmic membrane
regulates what goes in and out of the cell Made of phospholipids, cholesterol and proteins.
Pasteur and wine :)
saved french wine industry in 1857 The theory was that wine was made by a chemical breakdown of grape juice to alcohol Pasteur observed yeast in wine, and that soured wine contain populations of barely visible bacteria Pasteur proposed that yeast was involved in the fermentation of wine, and the bacteria caused it to spoil -Boiled grape juice, add back the yeast, and fermentation proceeds normally -‐ if all bacteria were removed, the wine did not go sour
is there a large or small number of bacteria that cause disease?
small
bacteria cells are the ___ cells
smallest
PROKARYOTIC CELL: inclusions
store nutrients for the cell or vacuoles for buoancy
theory of spontaneous generation: John Needham 1748
suggested that microbes arise spontaneously in mutton gravy. Needham had boiled the gravy and sealed the containers with cork, but yet microbes appeared -‐ his experiments were faulty. the heating of the bottle did not kill all of the microbes that were living there because: 1. some micorbes can survive hot temps 2. air has microbes, flasks werent covered
Why wouldn't bacteria grow on a petri plate?
the medium (agar) did not work for that microbe-not sufficient growing conditions
Translation
translation of the mRNA on a ribosome to make a protein
fungi, yeats, and bacteria are all....
unicellular
If you cant grow bacteria what can you do?
use genome sequencing
Virus takes over bacterial reproduction system
vDNA is converted into RNA, makes viral proteins, reform to create complete virus
steps of bacterial cell infection
viral DNA injected into bacterium, makes RNA, Mrna makes proteins producing the virus uses cell to reproduce virus, the cell will then lyse and produce 100s or 1000s of virus
Where does vancouver's dirty waste water go?
waste water treatment plant- relies on microbes to clean up the water
only way to eliminate infectious disease?
with vaccine. bc it protects people so they cant get the infection. -could have happened with poli- a few places wont give the vaccine for political/ religious reasons -only a few samples of smallpox around the world OR Eliminate source of disease EX) mosquitos and malaria
Did pasteurs work on wine shock the community?
yes! No one new that microbes could be agents of change (analogous to factories where chemical changes occur) -‐ and that bacteria appeared to make the wine sick Before Pasteurs discovery, physicians had thought that bacteria was an effect of disease (they appeared during illness) -‐ now Pasteurs work suggested they are the cause of disease