The structure of mAG, a monomeric mutant of the green fluorescent protein Azami-Green, reveals the structural basis of its stable green emission

Acta Cryst. (2010). F66, 485-489 (doi.org/10.1107/S1744309110011127)

[QYG chromophore] The unique QYG chromophore and the surrounding residues of mAG.

Azami-Green (AG) from the stony coral Galaxea fascicularis is a monomeric green-emitting fluorescent protein that is not a variant of Aequorea victoria green fluorescent protein (avGFP). The crystal structure of mAG has been determined at 2.2 Å resolution, which reveals the structural basis of the stable green emission of mAG. The conformation of the QYG chromophore, formed by Gln62-Tyr63-Gly64, is fixed by hydrogen bonds and van der Waals contacts with the surrounding residues. Particularly, His193, Arg66, and Thr69 contribute to the fixed conformation of the chromophore.

T. Ebisawa, A. Yamamura, Y. Kameda, K. Hayakawa, K. Nagata and M. Tanokura