I have done SeMet labelling of my protein using the Met auxotroph of BL21
It is called B834 (DE3) sold by Novagen (~$80). Mass Spec showed all mets
labelled (6). We used it as our second derivative all but the N-term Met
showed up. I included DTT in purification but not in crystallization. You
will probably have to vary conditions to get the best expression for your
protein. I used M9 minimal with twice the glucose suggested and 100mg/L
of the DL SeMet ( Its cheaper than the pure L) with no other amino acids
supplemented. Novagen gives a reference to (1992) Science 258, 987-991 for
using the B834 line for SeMet labbelling. Hope this helps.
