Roger Rowlett wrote:
>No air in the vessel, no foam.
What manufacturer/model do you use? I can't quite imagine a beater that
would have no air in the chamber but maybe there is something new under the
sun.
>Yield of soluble, active protein from broken cells is quite comparable or
>better than French press or sonication, but with no aerosols. The
>bead-beating unit is encased in ice water, and is used 15 s on and 45 sec
>off to minimize heat buildup. The solution still feels cold when
>transferred to centrifuge tubes for clarification. I suppose I could
>measure it next time to see how much it actually warms up during beating.
>
>Based on these observations, I conclude that the cell lysis by
>bead-beating is no more disruptive to proteins than a French press, but
>much, much faster. As a bonus, genomic DNA is sheared, so no more slimy
>lysates. We have used bead beaters exclusively since 1997 or so when I
>learned about them from a Swedish research group I was visiting. They are
>handy in both the teaching and research lab.
Interesting. I've never used bead beaters for E.coli work and only used it
once with yeasts. What I saw went well with what I read in the past from
others:
http://www.bio.net/bionet/mm/methods/1994-May/014416.html
Quote: "A comparison of sonication and beating showed that beating was much
harsher FOR OUR HEAT-LABILE ENZYME IN THE PLASTIC CUP than sonication".
Metal chamber is surely going to help but foaming is still a concern in my
mind.
- Dima
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