Editing Green fluorescent protein (section)

=== Autocatalytic formation of the chromophore in wtGFP ===
{{hatnote|For a synthetic analogue see also [[3,5-Difluoro-4-hydroxybenzylidene imidazolinone]].}}
[[File:GFP mechanism.svg|1200x1200px]]

Mechanistically, the process involves base-mediated cyclization followed by dehydration and oxidation. In the reaction of 7a to 8 involves the formation of an enamine from the imine, while in the reaction of 7b to 9 a proton is abstracted.<ref name=":2">{{cite journal | vauthors = Rosenow MA, Huffman HA, Phail ME, Wachter RM | title = The crystal structure of the Y66L variant of green fluorescent protein supports a cyclization-oxidation-dehydration mechanism for chromophore maturation | journal = Biochemistry | volume = 43 | issue = 15 | pages = 4464–4472 | date = April 2004 | pmid = 15078092 | doi = 10.1021/bi0361315 }}</ref> The formed HBI fluorophore is highlighted in green.

The reactions are catalyzed by residues Glu222 and Arg96.<ref name=":2" /><ref>{{Cite journal| vauthors = Ma Y, Yu JG, Sun Q, Li Z, Smith SC |date=2015-07-01|title=The mechanism of dehydration in chromophore maturation of wild-type green fluorescent protein: A theoretical study |journal=Chemical Physics Letters|language=en|volume=631-632|pages=42–46|doi=10.1016/j.cplett.2015.04.061|bibcode=2015CPL...631...42M |issn=0009-2614}}</ref> An analogous mechanism is also possible with threonine in place of Ser65.