Figure 3

Purification and mass determination of mCherry. (A) 4-12% Bis-Tris SDS-PAGE gel of Q-sepharose purification. Lane 1 - cleared cell-free extract; Lane 2- wash; Lane 3 - Benchmark ladder; Lane 4 to17 - gradient elutions. (B) 4-12% Bis-Tris SDS-PAGE of size exclusion purification. Lane 1- loaded protein; Lane 2 - Benchmark ladder; Lanes 3 to 17 - elution fractions. (C) ESI-MS ion envelope of purified mCherry protein, deconvolution calculation, and primary sequence of mCherry protein based on observed mass and protein sequencing. Amino-acids detected from N-terminal protein sequencing in bold, chromophore forming residues underlined, with the expected mass of the mature protein listed after the primary sequence.