Curiosity: competent cell and glycerol - (Dec/05/2006 )

Hello,

I am bit curious and I would like to know why we use glycerol 10% to make competent cell (mycobacteria). Is someone kwnow about it???

Thanks a lot


Biofred

cryopreservative as it reduces the rapidity of freeze, and as it decrease the melting temp allowed a quicker defrost.

we use DMSO rather than glycerol

Hello all thanks for your interest.

I know that glycerol is a cryopreservative but here it's probably not the subject.
To prepare competent cell of mycobacteria, we realise serial centrifugation of mycobacteria with glycerol 10%. Each time we reduce the volume of glycerol to obtain finally 1 ml of competent cell. Mycobacteria are very resistant so I don't think that it's problem to be at 4°C.
So why use this kinf of solution.

Thanks a lot


Biofred

not sure that i understand you , you mean ending with 1ml of competent cells in 10% glycerol ?
in one site i visit, they said that" glycerol increase the efficiency of transformation"..

ok, i guess it's for inducing osmotic change across bacteria walls , may be

or
for enhancing electroporation since it has 3 (-)vely charged OH groups, may be this has something to do with charge...think about it!

Hello strawberry,

yes I finish my competent cell in 1ml of 10% glycerol so thanks for your answer.

Thank you very much for your argument

Have a nice day

biofred

hi biofred..

i became so interested in your question about glycerol...if you get any info, PLZ let me know
thanx in advance..