the life and death of bacteria kelly l. shipley. funding and support received from…
TRANSCRIPT
The Life and Death of Bacteria
Kelly L. Shipley
Funding and support received from…
Today’s Agenda:
1) Introduction
2) Safety
3) The Life and Death of Bacteria
4) Basic Practice Techniques
5) Surveying Different Kinds of Media
6) Closing
Introduction:
All living things contain cells
Eukaryotes: more than one cell
Prokaryotes: one cell organisms
The Boring (Yawn!!) Eukaryotic Plant and Animal Cells…
The Exciting Bacterial Cell…
What are Bacteria?
Bacteria are prokaryotes, meaning they are only ONE celled organisms. They are very small and can be harmful or beneficial.
Follow along…
You have a picture of a bacterial cell at your desk.
Follow along with the following diagram, making sure you understand what each structure is and how it works.
Bacterial Cell Components…
Bacteria come in many different shapes and sizes…take a quick look…
How big are bacteria?
How many bacteria will fit on the head of a pencil, like the one you use every day??
1 MILLION bacteria could fit onto the tip of that one pencil!!
Bacteria can replicate easily…
To grow, bacteria divide and divide
and divide again.
Problem: If you started with only 1 bacteria cell, and it divided 10 times, how many bacteria would you then have??
Bacteria are everywhere…
Don’t panic!!
This is a good thing.
Bacteria are part of our lives, our ecosystem and our habitat!
Bacteria can cause diseases, like we all know…
Bacteria can also have beneficial uses…
As well as those beneficial uses…
There are many bacteria which humans need every day.
They live on us and in us and we NEED them!!!
They are called our “NORMAL FLORA”
Normal “flora”
Flora – microorganisms that are usually found associated with healthy body tissue
What does that mean? Normal flora are bacteria which
our body needs and play a “good” role to help us stay healthy.
Let’s look at the different areas “flora” live…
and then we will test them!!
Normal flora of the skin
Skin is considered a “harsh” environment for bacteria, why?
Bacteria like the areas of the skin which are moist; underarms, sweat glands etc.
Most are not harmful, but Acne…
Ie: Staphylococcus, Propionibacterium acnes,
Normal flora of the oral cavity
Streptococcus is a normal bacteria in your mouth
Other bacteria are also present that turn sugars into acids and cause dental plaque, cavities and decay
Brushing our teeth allows the normal flora to grow without build-up of other bacteria!!
Normal flora of the GI tract
The GI tract is the stomach, small intestine and large intestine.
Several different types of bacteria live in the GI tract and aid in digestion, movement of waste and absorption.
Ie: E. coli, Clostridium, Enterococcus faecalis,
Normal flora of the Urogenital Tract
Urethra (tube from which you urinate) have normal microorganisms present, but they can become “opportunistic” when there is a change in the environment and causing infection
Bladder and reproductive organs should always be sterile
Normal flora of the Respiratory Tract
Upper: oral cavity and throat microorganisms live in the areas around mucous membranes
Ie: Staph, Strept, and some gram negative
Lower: trachea, bronchi and lungs should ALWAYS be sterile, if not – pneumonia
Lab Information…Pay Attention
The following is an introduction to some of the media we will be using today…
Pay attention!!
Different Kinds of Media
We “grow” bacteria on different types of media.
“Media” means an environment inside a Petri dish that has certain characteristics
We will go over the types of media we are using today
MacConkey Agar Media
MacConkey is specifically designed to help bacteria that live on the skin to grow
“Gram Positive” bacteria
Grows pink, purple and white colored colonies
Mannitol Salt Media
Mannitol Salt is specifically designed to help “gut”
organisms grow.
“Gram Negative” bacteria
Yellow = gut organisms present
No change = no gut organisms present
Nutrient Agar Media
Nutrient media is NOT selective (G+ and G-)
This means that most all bacteria LOVE to eat nutrient agar
It is the most common media, and we will be using it A LOT!!
Now, let’s move on to our lab protocol.
We will be surveying different places where the different “skin” and “gut” bacteria grow
Where would be some good places to find either?
Where are some places to find them, where they really SHOULDN’T be?
Anti-Microbial Testing
Goal: To see how the products we use in our homes affect the different bacteria we know are around.
What types of products are out there?
Disinfectants
Disinfectants are substances that inhibit bacterial growth
THEY ARE ALSO HARMFUL TO HUMAN TISSUES!!
Disinfectants
Disinfectants are substances that inhibit bacterial growth
THEY ARE ALSO HARMFUL TO HUMAN TISSUES!!
Disinfectants
Disinfectants are substances that inhibit bacterial growth
THEY ARE ALSO HARMFUL TO HUMAN TISSUES!!
Antiseptics
Antiseptics are chemical substances that inhibit bacterial growth
THEY ARE NOT HARMFUL TO HUMAN TISSUES
Antiseptics
Antiseptics are chemical substances that inhibit bacterial growth
THEY ARE NOT HARMFUL TO HUMAN TISSUES
Antiseptics
Antiseptics are chemical substances that inhibit bacterial growth
THEY ARE NOT HARMFUL TO HUMAN TISSUES
What do you think?
Will antiseptics, which we use on our bodies, be more effective on Gram pos. or Gram neg. bacteria?
What about disinfectants?
How do each do against the bacteria on our plates?
How do you get your results?
Call me at 503-838-8209
E-mail me at [email protected]
Go to our website at www.wou.edu/