Fig. (7) Solubility of HT2-Rluc when expressed in bacteria. HT2 (34 kDa), HT2-Rluc (69 kDa), and Rluc (35 kDa) were overexpressed in E. coli KRX at 25 °C and then lysate fractions containing total (T) or soluble (S) protein were labeled to completion with the TMR-ligand (20 µM ligand, 1 h, 25 °C) and resolved by SDS-PAGE. Gels were imaged for both total protein (SimplyBlue, panel A) and the amount of functional HT2 or HT2 fusion (TMR fluorescence, panel B). Relative amounts of functional (TMR-labeled) protein were quantitated by fluorescence scanning (E_ex/E_em=532/580 nm). Overlaid arrows indicate bands of interest.