Supplies
What is the name of the nutrient media we used with our BB1 E.coli?
Laura Broth (LB)
A shallow, round dish used to grow cells or bacteria.
Petri Dish
E.Coli cells reproduce by
Asexual reproduction or binary fusion
How much bacteria should you use when preparing an overnight culture
1 colony
Why can't we take the OD600 of our 10-5 or 10-6 dilutions.
The absorbance reading would be too low and out of range of the machine.
This tool is used to inoculate liquid media
A loop
A nutrient-rich solution or gel that provides cells with what they need to grow.
Growth Media (Laura Broth in our case)
Why do we add antibiotics like ampicillin to our plates?
To select for only the bacteria with AMP resistance, preventing contamination.
What does it mean to inoculate something?
Add bacteria to a liquid media.
You should use this to blank the spectrometer before measuring the absorbance of your overnight culture
Laura Broth (LB)
This is used when you want to plate a lawn of bacteria
Cell Spreader
the unwanted presence of bacteria, fungi, or other organisms in a cell culture.
Contamination
What is the goal of streaking for single colonies?
To isolate a single strain of bacterial cells that are genetically identical
Why do you store petri dishes upside down?
To prevent condensation from accumulating on the couture.
Name the conversion factor to go from OD600 value (AU) to Cell concentration (cells/ml)
1 AU = ~8 x 108 cells/ml
We added this to our growth media to select for the BB1 E.coli strain.
Ampicillin
A jelly-like substance often used as a solid growth medium for microorganisms.
Agar
In this phase bacterial cells harvest nutrients from dead bacterial cells because there are no more nutrients available in the growth media
Death Phase
CFU stands for
Colony forming units
How do you calculate % viability
CFU/Total Cell Concentration * 100%
This machine is used to help grow liquid cultures overnight.
Shaking Incubator
Procedures used to prevent contamination by unwanted microorganisms when working with cells.
Aseptic Technique
Bacteria in the phase use the nutrients in the growth media to create new bacterial cells.
Exponential Phase
You should do this if your plate has medium density of colonies
Cut the plate into quadrants, count one quadrant and multiply that number by 4
OD600= 0.5 AU what is the estimated cell concentration?
4 x 108