view article

Figure 5
The chromophores of gfasPurple (purple), amilCP (dark blue), eforRed (red) and spisPink (pink). Residues forming the chromophores are labelled in grey. (a)–(d) Composite omit maps (2mFoDFc) contoured at 1.5σ showing the electron density for the chromophores (sticks) and the preceding residue in the amino-acid chain (lines). The subsequent amino acid is also shown as lines. Atoms and bonds discussed in the text are labelled in the chromophore for gfasPurple, and trans and cis chromophore conformations are labelled for amilCP and eforRed. (e)–(h) Side view showing the peptide link between the chromophore and the preceding amino acid (labelled in grey with *), suggesting N-acylimine formation (black arrowhead) in gfasPurple, amilCP and eforRed but not in spisPink (purple arrowhead). (i)–(l) Chemical structures of the chromophores in gfasPurple, amilCP, eforRed and spisPink, respectively, inferred from the electron density. The ionized form is shown for eforRed as in other related red fluorescent proteins (Miyawaki et al., 2012BB31), and N-acylimine formation is highlighted in the same way as in (e)–(h).

Journal logoSTRUCTURAL
BIOLOGY
ISSN: 2059-7983
Follow Acta Cryst. D
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds