1kou
From Proteopedia
Crystal Structure of the Photoactive Yellow Protein Reconstituted with Caffeic Acid at 1.16 A Resolution
Overview
A structural study is described of the photoactive yellow protein (PYP) reconstituted with the chromophore derivative 3,4-dihydroxycinnamic acid. The crystal structure of PYP reconstituted with this chromophore at 1.16 A resolution is reported in space group P6(5). This is the first high-resolution structure of a photoreceptor containing a modified chromophore. The introduction of an extra hydroxyl group in the native chromophore (i.e. p-coumaric acid) appears to perturb the structure of the hybrid yellow protein only slightly. The chromophore is bound by the protein in two different conformations, separated by a rotation of 180 degrees of the catechol ring. In combination with available spectroscopic data, it is concluded that the caffeic acid chromophore binds to the protein in a strained conformation, which leads to a faster ejection from the chromophore-binding pocket upon pB formation.
About this Structure
1KOU is a Single protein structure of sequence from Halorhodospira halophila. Full crystallographic information is available from OCA.
Reference
Structure of the photoactive yellow protein reconstituted with caffeic acid at 1.16 A resolution., van Aalten DM, Crielaard W, Hellingwerf KJ, Joshua-Tor L, Acta Crystallogr D Biol Crystallogr. 2002 Apr;58(Pt 4):585-90. Epub 2002, Mar 22. PMID:11914481 Page seeded by OCA on Fri May 2 22:59:53 2008