Growth and expression profile of the TM4-Cx43CT in minimal media necessary for NMR structural studies. Growth curves (panel A) and electrophoretic profile of total cellular proteins (panel B) obtained from the E. coli strain C41(DE3) expressing the TM4-Cx43CT in different minimal media. The lanes in the SDS-PAGE gel correspond to cells grown in the following media: lane 3, ISOGRO, lane 4, 15N minimal media, lane 5, 15N13C minimal media, lane 6, Luria broth (LB), and lane 7, unlabeled minimal media. All minimal media were made as outlined in (35). Lane 1 contains the protein molecular weight marker. Lane 2 is the control, uninduced (no IPTG) cells grown in LB. The arrow represents the location of the TM4-Cx43CT.