I am currently working on a project where I need to use a purified phage to target S. aureus, and we are stuck on what the best option for purifying the phage stock would be. Does anyone have any suggestions? I've read different opinions from various papers ranging from saying CsCl is a good option and others saying it is the worst option.
Easiest option would be to use a fine syringe filter to isolate phages from a culture and then do serial dilutions before applying to a lawn of non-motile S. aureus. You then pick single plaques and do a few passages. PEG precipitation can then be used to concentrate your stock.
It depends on what you intend to do. CsCl is a good option for some phages and especially if you intend to do biochemical work and need very pure phage stock free of contaminating bacterial crud. But it is much more work, requires high titer and may inactivate some phages. If you are doing "biological work" then there is not any need to CsCl purify. In fact you don't really need to purify beyond sterilization, but PEG precipitation is a good way to concentrate as Robert Adolf Brinzer mentions.
First add chloroform to phagestock ( this step only if u are sure it’s non-enveloped phage )1:10 then centrifugation for 12 minutes
take supernatant and purify it by filter syringe .22 ul and put in sterile well covered flask or tube
and u can also make serial dilution by sterile dist water and perform the plaque assay and takeo one plaque from plate and then add the fresh host bacteria to propagate phage stock
Have a good day!
- Badges
- Science topic
- Similar topics
- Medicine
- Disease
- Infectious Diseases