Via figshare:
E. Coli Growth in DI, DDW, D2O, 30% D2O, and 60% D2O. Anthony Salvagno. Figshare.
Retrieved 23:35, Apr 27, 2012 (GMT)
hdl.handle.net/10779/51fcd2f94fd7464449ee0f794642214c
I’ll post some interpretations here later…
Via figshare:
E. Coli Growth in DI, DDW, D2O, 30% D2O, and 60% D2O. Anthony Salvagno. Figshare.
Retrieved 23:35, Apr 27, 2012 (GMT)
hdl.handle.net/10779/51fcd2f94fd7464449ee0f794642214c
I’ll post some interpretations here later…
24h Growth of E. coli in D2O, DDW, DI, 30% D2O, and 60% D2O. Anthony Salvagno. Figshare.
Retrieved 19:23, Apr 27, 2012 (GMT)
hdl.handle.net/10779/5e1e8fdaeeb4d7161c1f73990d42147e
Today I’ll be taking time points of the e. coli growth every hour in LB suspended in DI, DDW, D2O, 30% D2O, and 60% D2O. I’m going to follow my protocol from yesterday, where I blank for the water type, before I measure the absorption for that water type.
I’m not sure what to think about the values for the overnight growth. E. coli grew in 99% D2O, which was rather surprising. Maybe it isn’t. All there needs is to be 1 cell that grows and then there will be a colony. This makes me think that growing e. coli in 99% D2O and switching that colony to DDW wouldn’t reveal too much. I may have to do multiple generations of growth in D2O before I switch growing medium to make sure the colony is fully adapted to life in D2O.
Also that makes me think that my setup from yesterday wasn’t so optimal. Perhaps by growing cells in each water type initially, I’ve just insured that they will all grow at the same rate and there will be nothing to reveal here. Hmmm, I’ll have to think about this. I feel like I’m trying to trick e. coli, but it somehow is outsmarting me.
No sir, I don’t like it…
Data on figshare:
24 hour growth of e. coli in DDW and D2O. Anthony Salvagno. Figshare.
Retrieved 22:57, Apr 26, 2012 (GMT)
hdl.handle.net/10779/6a26c1c4c7e487101f894fe53c5e8473
Notes:
Tomorrow I’ll be running the same experiment I ran yesterday, only this time I did a much better job preparing the cultures and the liquid media. The broth setup can be found here.
Today I initialized the starter cultures in each water type. The liquid media was made in 99% DDW and 99% D2O and the partial medias are a mix of each water type in the appropriate ratios. Here is my setup:
Tomorrow I’ll be repeating yesterday’s experiments with each of these samples, taking time measurements every hour all day long. Happy, happy, joy, joy!
Yesterday it occurred to me that I couldn’t autoclave LB media made with DDW or D2O because of D-exchange. So I had to come up with a solution which prompted me to ask the world (thank you internet). Through the power of open science (victory for ONS!) I was able to get some comments that said I should use a 0.2 micron filter:
@Thescienceofant two points 1. you can grow E. coli static (no shaking) 2. why not make(or buy) 10x LB and use sterile-filtered D2O?
— Warren G. Lewis(@Luminescer) April 26, 2012
Well that is what I did and here is my protocol:
Presto!
From FigShare:
E. coli growth in D2O, DDW, and DI. Anthony Salvagno. Figshare.
Retrieved 01:18, Apr 26, 2012 (GMT)
hdl.handle.net/10779/e186403d944367bcbf5bdd9ed6977a88
The handle is a broken link for some reason so here is the direct link until that gets resolved.
And some notes:
For tomorrow, I don’t think I’ll be redoing this experiment. So I’ll just do another starter culture and try it for Friday. I’ll also do cultures in DDW, 30% D2O, 60% D2O, and 99% D2O.
Now big important question. Should I autoclave the DDW and D2O LB Broth mixes? Keep in mind the major fear of deuterium exchange.
I’m going to need to amend my category system. I feel like it makes very little sense to have it organized the way it is. I’ll have to spend some time thinking about how I want these experiments arranged.
Regardless, I’m doing an extension of the experiments from last week. This time I’m going to compare the growth from a regular LB broth sample, to growth in DDW and D2O. Here is my setup:
I’ve already made some mistakes in this experiment:
The one positive is that I did starter cultures is 30% D2O and pure DDW so that I can redo this experiment tomorrow with hopefully much better results. I’ll be preparing the LB broths later today with a quick protocol of that.