Re: [ccp4bb]: Culture in large scale

["Francisco J. Enguita" <fenguita@itqb.unl.pt>]

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It looks like the expression of your protein in a soluble manner is
dependent on the oxygen transfer rate. When you increased the volume of
the cultures, if you did not maintain the volume/surface ratio, you got
lower oxygen transfer rate.

Try to use bigger Erlenmeyer flasks for bacterial cultures with low
amount of culture media. Let's say a 500 ml erlenmeyer flask with 100 ml
of culture media (this increase the surface contact for oxygen
transfer). Your also could work with higher agitation speeds in your
shaker. I used to work in 500 ml flasks with 100 ml of culture media at
250 rpm in a rotaty shaker.

I hope it helps

Good luck

Francisco

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Francisco J. Enguita, Ph.D.
Protein Crystallography laboratory
Instituto de Tecnologia Química e Biológica
Ap. 127
2781-901 Oeiras
PORTUGAL
Phone : 351-21-4469669
Fax : 351-21-4411277
E-mail : fenguita@itqb.unl.pt

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