Sorting Bacteria

Barren, Phil (BarrenP@MedImmune.com)
Fri, 4 Apr 1997 10:00:56 -0500

Flowers!

Does anyone have any experience with sorting bacteria (Streptococcus)
on a stream in air flow cytometer. I am using a
FACSTAR Plus.

What I think I need is a dye that will allow me to counter stain all
the bacteria (preferably live) to be used in conjunction with a dim
surface label, and then sort on the surface labeled positives. The
counter stain would need to be dim so as not to interfere with the dim
surface label.

I have tried to sort with a SSC log threshold. and this does not work.
As soon as I vibrate the stream I loose all low end resolution which
is where my bacteria are.

I need to use a fluorescent trigger to threshold on, this would be less
sensitive to stream vibrations which is what I assume is killing me on
the log SSC threshold.

Just a note all my Scatter parameters are on logarithmic amplification.

Thanks in advance for your time and energy

Philip Barren

Pb