Field of Science

Titering my lysates

Planning today's work:

Titering the phage lysates should be a no-brainer, but it's been a long time since I worked with phage so I'd better think things through before I do it.

I have 15 ┬Ál of each of 5 phage stocks ('lysates').  The original titers (plaque-forming units/ml, pfu/ml) are written on the tubes - they range from 6x10^5 pfu/ml to 2x10^11 pfu/ml.  But the lysates are probably quite old (maybe 2 years, maybe more), so their titers may have dropped a lot.

I think I'll do one poured-lawn plate of each, using an amount of lysate that should be about 1000 pfu according to the original titer.  And I'll do a spotted-lawn plate for each phage, using undiluted lysate  and a range of dilutions.


I'll dilute the lysates in the same YPS medium I've grown the cells in.  It has calcium and magnesium added so should be fine for typical phage.

No comments:

Post a Comment

Markup Key:
- <b>bold</b> = bold
- <i>italic</i> = italic
- <a href="http://www.fieldofscience.com/">FoS</a> = FoS