Results:
And the setup for day 37:
I made glycerol stocks of the yeast that started the entire D2O adaptation experiment, and now that I may have a D2O adapted strain I made another glycerol stock for safeguarding. I used the protocol found here for reference, with the exception that I doubled the recipe.
Via figshare:
Yeast Adaptation Day 33. Anthony Salvagno. figshare.
Retrieved 21:48, Oct 31, 2012 (GMT)
http://dx.doi.org/10.6084/m9.figshare.96961
I assure you this data was uploaded yesterday once I took the 24 hour measurements of the cells. That measurement was actually an additional data point I felt added to the data and provided the typical shape of the growth curve of yeast.
With regards to this data, it seems the D2O strain that I’ve been working on is adapting to D2O and its growth is not all that different from yeast grown in DDW, which in past experiments is definitely not the case (Day 1, Day 6, Time Trial 5, Time Trial 4, etc). I compared this growth to the growth of the previous experiments of Days 1 and 6 and got this figure, which shows the results side by side.
More data is needed (and will be attained) but this looks pretty good. Onward!
Yesterday I uploaded this graph:
I hadn’t had the time to post any observations or thoughts, but I just wanted to get the data out there. Well now I have time, so come sit, stay awhile, and listen!
This graph compares the growth of yeast in D2O at 3 different dates: Day 1, Day 6, and Day 33 of the adaptation experiment. Each data set is from the time trials conducted on those dates. So the data shown above is a comparison of the hourly yeast growth of those three different dates.
While I’m remain skeptical that this data shows the yeast I’ve been cultivating for the past month has in fact adapted to D2O, it does seem pretty obvious. The growth of yeast in five hours after being isolated in D2O for 33 days is significantly different than normal (H2O adapted) yeast grown in five hours. Granted the starting cultures are of differing cell counts, the growth rates of all samples are drastically different.
As I mentioned earlier, tomorrow (hopefully) I’ll be running another time trial experiment that will compare the (potentially) D2O adapted yeast to yeast adapted to H2O grown in D2O and H2O adapted yeast grown in DDW (both of these have been inoculated as starter cultures). Hopefully that provides further evidence that this strain of yeast is in fact D2O adapted. If I have in fact attained a D2O adapted strain of yeast, then I will get to move on to some exciting experiments to analyze phenotype changes in the D2O adapted yeast when compared with H2O adapted yeast.
Back on track here are the Day 35 results:
I set up the next day’s experiment with some added twists. I have a total of 9 samples for tomorrow, 3 samples of each water type:
The first set of samples (1 of each type) is prepared as I normally prepare an experiment: 9ml of ypd with 1ml of ypd with culture.
The second set of samples (1 of each type) is 9ml of each water type with a culture inoculated from the Day 34 samples. By this I mean instead of adding 1ml I added whatever the inoculating sticks can hold and swooshed it around in the sample. The goal of this is to see how much yeast can grow in 24 hours from a small number of cells. In my original starting culture samples, the cells in D2O would grow astronomically slower than in DDW and my assumption is that if my cells are truly adapted the difference in growth won’t be so drastic.
The third set of sample (1 of each type) is 9ml of each water with a culture inoculated from glycerol stocks I made of samples from the first week of experiments. All the samples are inoculated from DDW grown yeast. The purpose of this set is so that I can do a time trial of the (potentially) adapted yeast compared to nonadapted yeast grown in D2O and with DDW yeast. And if that experiment reveals that my yeast is adapted to D2O, I would like to compare yeast grown in D2O to yeast adapted to D2O and to yeast grown in and adapted to H2O.
Exciting times ahead!
I was way out of it yesterday. I completely forgot to write up my Day 34 adaptation results! Rest assured I did the experiment and documented the results and set up the next day’s experiment, but just missed the recording function. Anyways here is what you are clamoring for:
I also set up the experiment for Day 35 and added a special guest: DDW YPD (1.362 at 0h), mostly because I had the time trial experiment from the day before and I wanted to compare another 24 hour growth to DDW adapted yeast. So the day 35 results will feature 3 samples:
It looks like the yeast is beginning to adapt, or has adapted and is ready for the next phase of the experiment. I’ll write more information later because I need to eat, but enjoy this simple graph and feel free to leave some comments below.
In addition to the Day 33 daily adaptation I’m going to run an hourly experiment to see if the yeast has adapted or evolved or changed. I’ll be looking for a growth rate that is faster than in previous trials, and more comparable to yeast growth in DDW YPD. Here is my setup:
Unbeknownst to most of the world, I’ve had a secret agent specially trained to carry out my experiments while I’ve been away. Before I left for Seattle, I trained my lab colleague Nadia to do the 24 hour yeast adaptation experiments. She’s been keeping the experiment up to date and posting the results in the Google Doc I set up back on Day 1. THANK YOU NADIA!!! You can see the updates at that link or just read down:
This morning is my first day in the lab since my departure and I’m picking up right where I left off, the 27th Generation of yeast in the table above are my first recorded values based on Nadia’s efforts.
Here are the results in typical fashion:
The experiment was setup in typical fashion: