E. coli Protein Expression Services


E. coli Expression Testing

Your expression construct will be used to transform E. coli followed by isolation of individual colonies and establishment of glycerol stocks. Cultures will be inoculated with overnight seed cultures and grown at desired temperature until mid-log phase.  Target gene expression will then be induced by addition of IPTG (inquire for other inducible promoters) in the positive control culture with growth continued for 3 h to 16 h.  A negative control (i.e. no IPTG) will be cultured alone with the test cultures. Cells will be harvested and processed to yield total, soluble, and insoluble protein fractions that will be analyzed by SDS-PAGE.  Test parameter choices are media (e.g. LB, 2YT, TB and many others), temperature, and induction time.

Enhanced expression testing services includes affinity pull down such as Ni-NTA, Glutathione and FLAG.  Please enquire.

Delivered: Summary with image(s) of SDS-gels.
Time: 3-4 days.

E. coli Fermentation

One liter of media will be equilibrated to desired growth temperature and inoculated with 10 ml of starter culture in a 3 L baffle-bottomed high-speed shake flask.  Cell density will be monitored (OD600nm) and IPTG (or other inducing chemical) will be added at mid-log phase and growth continued for 3 h to 16 h. Cells will be harvested and frozen at -20°C. Media choices are LB, 2YT, TB, and many others (please inquire).

Delivered: Weighed & frozen cell pastes.
Time: 3-4 days.