Field of Science

It's not the water, nor the tubes, nor the parafilm...

So far my GFAJ-1 cells grow great on agar plates.  I've tested several brands of agar (Bacto, MBP, and some cheap old stuff (Mikrobiologia?) that we only use for E. coli.  They also grew great on agar plates that had been overlaid with 2 ml of the liquid medium, to greater than 10^8 cells/ml!

But they won't grow at all (and I suspect they die) in the liquid media I made, regardless of whether the medium was made with tap water or distilled water.  It doesn't matter whether the culture tubes were washed before being used, nor whether the medium is in a plastic petri dish sealed with parafilm instead of a culture tube.

Adding the trace elements mix to the original batches of medium didn't let the cells grow, but the cells did survive better (maybe even grow a bit?) in a new batch of liquid medium I made up with trace elements.  Tonight I'm testing whether they'll grow better in a plastic tube with a tightly sealed screw cap; the control is an identical tube with a loose-fitting cover.

The vitamins we ordered have arrived so I was going to text the full ML60 medium used by Wolfe-Simon et al.  But I just discovered that I'd forgotten to put PABA (4-aminobenzoic acid) on the list.  Maybe I can 'borrow' some from another lab, but if not I'll have to wait till next week.

No comments:

Post a Comment

Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="">FoS</a> = FoS