PMID: 12623015 , Related PDB ids: 1MOU, 1MOV

Authors:

Prescott M, Ling M, Beddoe T, Oakley AJ, Dove S, Hoegh-Guldberg O, Devenish RJ, Rossjohn J

Title:

The 2.2 A crystal structure of a pocilloporin pigment reveals a nonplanar chromophore conformation.

Journal:

Structure. 2003 Mar;11(3):275-84.

Abstract:

Reef-building corals contain host pigments, termed pocilloporins, that function to regulate the light environment of their resident microalgae by acting as a photoprotectant in excessive sunlight. We have determined the crystal structure of an intensely blue, nonfluorescent pocilloporin to 2.2 A resolution and a genetically engineered fluorescent variant to 2.4 A resolution. The pocilloporin chromophore structure adopts a markedly different conformation in comparison with the DsRed chromophore, despite the chromophore sequences (Gln-Tyr-Gly) being identical; the tyrosine ring of the pocilloporin chromophore is noncoplanar and in the trans configuration. Furthermore, the fluorescent variant adopted a noncoplanar chromophore conformation. The data presented here demonstrates that the conformation of the chromophore is highly dependent on its immediate environment.