Protocol Online logo
Top : Forum Archives: : Protein and Proteomics

Ultrasonic bath - bacteria lysis using a ultrasonic bath (Feb/15/2007 )

Hi,
I'm trying to lyse small bacterial samples (1ml) and don't have a convencional sonicator (with a probe). The only thing I have is a ultrasonic bath but I'm not sure how to use it. Did anyone used this for bacteria disruption successfully?

Any advice welcome, thanks!

-rosangelafrita-

Do you mean the one with water bath? Apparently, it wouldnt be as effective as the sonicator with a tip. You really need a very high amplitude in order to disrupt the cells. I think you can try by doing about 5 times with short burst on the ice? wink.gif

-timjim-

QUOTE (timjim @ Feb 15 2007, 11:49 AM)
Do you mean the one with water bath? Apparently, it wouldnt be as effective as the sonicator with a tip. You really need a very high amplitude in order to disrupt the cells. I think you can try by doing about 5 times with short burst on the ice? wink.gif


So, I just put the eppendorfs on water for short periods of time? I tried that at the maximum amplitude and it didn't seem to work. How long should I leave the tubes on the bath?

-rosangelafrita-

Actually I am not too sure as I used detergent lysis instead of sonicator. My supervisor mentioned to me that water bath sonicator will never work because it doesnt have a very high amplitude compared to the tip one. But I tried myself anyway thinking that it might able to lyse the cells. It doesnt really work as effective as detergent lysis. What I did was put my samples in the water bath and sonicate for like 10 seconds and put it back on ice for 20 seconds. Then I repeated about 4 times. So I guess my supervisor is right about it. wink.gif

-timjim-

ok, thanks. I also think detergent lysis is better but my supervisor wants me to try sonication instead!

-rosangelafrita-

If you have the sonicator with the tip. That will be much better. The other method perhaps you can try is the Freeze Thaw method if you are lysing a gram negative bacteria. Hope it helps. happy.gif

-timjim-

Do you have access to liquid N2, or dry ice? If so, try freeze-thaw (the dry ice needs to be mixed with ethanol, it gives you about -80C liquid). Resuspend your cell pellet in lysis buffer containing some lysozyme and DNase I (and protease inhibitor like PMSF), then freeze. Thaw in a water bath for a few minutes, and repeat the process a couple of times. Spin down hard to clarify the lysate.

I don't think the ultrasonic baths are anywhere near strong enough to disrupt cell walls.

-swanny-

I agree with swanny that ultrasonic baths are as effective as the sonicator.

If ultrasonic bath is strong enough, you will need to wear a ear plug (to prevent damaging your eardrums) when cleaning equipment.

I think swanny is right about using freeze and thaw method to make the cell lyse if you don't have a sonicator.

-Minnie Mouse-