precipitating bacteriophage-E79

[Tom Knight]

Kanwaldeep Dhaliwal <kdhaliwa from staffmail.ed.ac.uk> writes:
> can anyone help? Iam having trouble precipitating E79 phage (specific
> for PAO1).
> i have lystaes with a titer of 10^22 per ml of E79 to which i added
> some chloroform and kept at 4 degrees C, and am trying to PEG
> precipitate with 20% PEG 800 and 2.4 M NACL in PBS
> then on ice for 30 mins and spin at 9000G for 20 mins
> i never get a pellet I can see

I sincerely doubt that you have 10^22 phage/ml.  Think about the MW of
the phage, probably many megadaltons.  This means that 1 mole of phage
weighs more than 1000 kg.  You claim to have 1/60th of a mole per ml,
which would be at least 15 Kg of phage per ml.  I don't think so.

I believe you want to use PEG 8000 rather than PEG 800 for the
precipitation.