Shaker rotation to grow bacterial cultures? - (Mar/23/2005 )

Hello guys,
This might seem like a basic question but it is quite intriguing. What is the maximum rpm that you would recommend on a rotary shaker to grow bacterial cultures?
I have seen some of colleagues jack up the speed to 300rpm! This seems to be too much in my view. I have never crossed 240 or 250rpm.
I am sure there is a max to the speed? There has to be some tolerance level for the bacteria?

Any views/suggestions? Thanks in advance.

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hi
here is what i do and works in my hands...
after electroporation i let bacterias shaking 45' at 300rpm
then i do at 200-250rpm

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Tolerance level for the bacteria? I guess your shker would break before any bacteria die (they survive in your tabletop centrifuge >10 000rpm....).

The limits are:
- Your flasks/tubes: you don't want the culture to go over the top.
- The shape of your tubes: Erlenmeyers are reasonably agitated at much lower speed that any microtubes(it's hard to avoid bacterial sedimentation in a full microtube). Falcon tubes are between these extremes, and you achieve better results at lower speed if they are not vertical in the shker.

HTH

Patrick

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