culture plate storage - cloning (Feb/06/2008 )

Hi!
i have Luria Agar ( containing kanamycin 35ug/ml) plates of E.coli BL21 De3 pLysS having recombinant pET vector kept at 4 degree celcius.
my question is how long can i use this plate safely for growing cultures for gene expression/ induction studies.
thanks in advance!

If you seal the plate in parafilm or in a plastic bag to retard evaporation, it will be viable for 2 weeks easily. Beyond that, you should probably be making a frozen glycerol.

2 weeks if properly sealed.