Figure 3.

Spectral properties of bilin adducts of PCMs of recombinant ToTCCP, ScTCCP, and GlTCCP proteins indicate differences in the ratio of two spectrally distinct 15E photoproducts in the TCCP family. Absorption spectra of PCMs of ToTCCP (A), ScTCCP (B), and GlTCCP (C) incorporating PCB (solid line), BV (dotted line), or PΦB (dashed line) are shown in 15Z dark-states (blue) and 15E photoproducts (orange) in standard assay buffer at pH 8 (see “Experimental procedures”). Dark-minus-light difference spectra at pH 8 for native ToTCCP (D), ScTCCP (E), and GlTCCP (F) were obtained from panels A–C, respectively. Zinc in-gel fluorescence and Coomassie Brilliant Blue (CBB) images of acid-denatured TCCPs (G) are shown. SDS-PAGE gels imaged by zinc-dependent in-gel fluorescence (upper panel) and after staining with CBB (lower panel) are shown. Molecular mass markers (M) in kDa are indicated on the ordinate on the right side.