Raw Experimental Notes June 2016

6/27/2016 Magi, Patrik, Crystal, Ben

• Today we poured new YPD+5FOA plates because the plates we poured last week were infected (picture coming soon)
• We used 100mL of distilled water with 2g of agar and 5g of YPD.
• We autoclaved the solution and filters Ben got for the 5FOA
• The filters can be used to sterilize the 5-FOA
• We added 5mg of FOA dissolved in DMSO

6/24/2016 Patrik, Crystal, Kristen

Next Steps:

• re-make YPD-5FOA plates (autoclave DMSO and filter - need to get 0.45 micron nylon filters)
• continue with streaking
• hash out planning steps for transformation

Observations:

• three yeast strains grown to approximately equal volumes (Josiah, Johan, and Baker)
• SD-URA and YPD look good; all three YPD+5-FOA were contaminated, and it appears to be contaminated within the agar, so presumably the 5-FOA or DMSO introduced something; need to get 0.45 micron nylon filters for sterilization and plates need to be re-poured

Procedure:

• vortexed yeast strains to suspend

Prep:

• sterilized biosafety cabinet & prepped bleach/IPA container for disinfecting

Planning Steps for Transformation:

• 5-Hour Growth
• Wash out growth medium with salts
• Put on electroporation buffer
• Set up and do electroporation (need to rally help from Johan and other folks)
• Put on recovery medium (1/2 hr)
• Plate out on defined media with URA & compare to ones with Leu (we have enough plates)
• Put in incubator

6/22/2016 Magi, Patrik, Kristen, Johan

Completed the following steps (as per plan!)

• Prepared define medium plates and broth
  • For the plates: we mixed SD-URA+ glucose+Agar
  • For the broth: we mixed SD-URA+ glucose
• Poured 20 plates and 3 tubes of YPD broth
• Saved left over broth in fridge (to be used later)
• Cultured yeast in medium
  • Culture control yeast in defined medium overnight (12-72 hrs)
  • Culture mutant yeast BY4741 in YPD overnight (12-72 hrs)
  • Culture mutant yeast BY4742 in YPD overnight (12-72 hrs)

The three liquid cultures are currently in the 30C incubator, shaking at 150rpm

Action Item: Purchase Agar and large plates

Additional Notes:

• Small plates were used (because we are out of large size plates). The small plates have a total volume of 14mL. We poured approximately 5mL per plate
• The three liquid cultures we did last week are in the black fridge, along with all the small plates, the plate with BY4742 that we got from Josiah, the big bottle of YPD broth, and the remaining flask of SD-URA broth.

6/20/2016 Magi, Patrik, Kristen

Planning for Next Steps: Verification of Yeast (Streaking) and Transformation Objective: Verify the phenotype of two yeasts by growing them on various media

Streaking:

Day 1 Wednesday (starting at 6): 3-4 hrs

• Step 0. Make & Autoclave define (SD-URA) medium broth (2 hrs) (x2 for plates and broth)
• Step 1A. Culture control yeast in defined medium overnight (12-72 hrs)
• Step 1B. Pour plates

Day 2 Friday 5 pm

• Step 3. Measure optical density & normalize amount that we grow on each plate (1/2 hr): Need to get someone to help with that
• Step 4. Streak on different plates (1/2 hr)
• Step 5. Freeze remainder (1/2 hr)

Day 3 (Sun/Mon) after 1-2 days to take pictures of plates to double-check that yeast and plates work correctly

• Take pictures of all plates

Transformation: goal is to do this by Monday 6/27

• Figuring Out Protocol & Confirming Reagents

Day 1 (some Monday when Patrik can come in in the morning) Step 0. 5 Hour Growth in Specific Medium (may require autoclaving)

06/15/16 Patrik & Magi

Several of the standard URA- yeast strains grow poorly in defined medium, because the have a leucine uptake defect. So we decided to pour some plates with defined medium and double the normal amount of leucine. Standard leucine concentration in SD is 120mg/L.

See:

Commonly used Saccharomyces cerevisiae strains (e.g. BY4741, W303) are growth sensitive on synthetic complete medium due to poor leucine uptake

http://onlinelibrary.wiley.com/enhanced/doi/10.1111/j.1574-6968.2007.00798.x/

Ingredients:

• 7.47g/L SD-URA-Glucose
• 20g/L glucose
• 20g/L agar
• 120mg/L leucine

Adding leucine at 120mg/L in a 160mL mix which equates to 19.2mg of Leucine- used 23.4mg (accuracy achieved on scale)

In 160mL we added: 23.4mg of Leucine, 3.2g of Agar, 1.15g of SD-Ura-Glucose and 3.2g of Glucose

Added to autoclave until it reaches 121C then removed by Patrik.

Next steps:

• Get ready for Electroporation:
  • Figure out the ideal timing to perform electroporation- ideally during the log phase of the yeast growth phase

6/13/2016 - Magi, Kristen, Patrik, Sean

Experiment: Yeast Revival & Confirmation of Correct Yeast

Tasks:

• 0. Revive yeast cultures (Patrik did this previously, and confirmed that the baker's yeast (control) was able to produce its own Uracil; however, the revived cell did not appear to exhibit much growth, so additional 500l of yeast strain was added to the tube, and another tube was also made) - Complete
• 1. Prepare agar mixes (done) - Complete
• 2. Pour Plates - Complete
• 3. Streak plates & then check for colony growth - Pending

ToDo(s):

• Immediate: Confirm that the yeast cultures exhibit the correct behavior (ability to grow in 5-FOA and not in SD-URA)
• Next Steps: Make new glycerol stock
• Later (Next Week): transformation (assuming everything goes well)

• Found previous prepared plates (large & labeled RVC)
• Check for contamination: 4 -URA + Glucose (colorless), 5 (mixture of YPD + YPD + FOA):> decided not to use these and to repaired
• Pouring medias: YPD, SD (-Ura -Glu), 5-FOA; decided to pour whole pack (25), so 8 plates of each
• Volume of plate: 700 ml per plate; decide to make 20 ml of working media (so 20 x 8 plates = 160 ml)
• YPD = 50 g/L; SD- = 7.47 g/L; (need to add 20 g/L of glucose); 5-FOA: 0.5% see prep calculations here: https://docs.google.com/spreadsheets/d/1SRrFP4an20c3uaTYZRlUEeXM6md2O3ES7In1e4Jjqnk/edit#gid=0

• Last night Patrik started some cultures: 1) control 2) revived culture (from the glycerol stock): should be able to grow in presence of 5-FOA but not in SD-URA
• Autoclave settings: 121 C (setting at 21)
• agar (non-LB) is added at 20 g/ml

Practices:

• Plates should be stored upside to avoid collecting contamination on lids)
• Contaminated plate submerged in bleach water
• Preparing bleach: 1:10 bleach to tapwater (grab from restroom; not hand-washing water)