6T6M

Y201W mutant of the orange carotenoid protein from Synechocystis at pH 5.5

Summary for 6T6M

• Entry DOI: 10.2210/pdb6t6m/pdb
• Related: 6T6K
• Descriptor: Orange carotenoid-binding protein, beta,beta-caroten-4-one, GLYCEROL, ... (5 entities in total)
• Functional Keywords: orange carotenoid protein, photoactive protein, mutant, plant protein
• Biological source: Synechocystis sp. PCC 6803
• Total number of polymer chains: 1
• Total formula weight: 37253.63

Authors

Sluchanko, N.N.,Gushchin, I.,Botnarevskiy, V.S.,Slonimskiy, Y.B.,Remeeva, A.,Kovalev, K.,Stepanov, A.V.,Gordeliy, V.,Maksimov, E.G. (deposition date: 2019-10-18, release date: 2020-11-18, Last modification date: 2024-01-24)

Primary citation

Yaroshevich, I.A.,Maksimov, E.G.,Sluchanko, N.N.,Zlenko, D.V.,Stepanov, A.V.,Slutskaya, E.A.,Slonimskiy, Y.B.,Botnarevskii, V.S.,Remeeva, A.,Gushchin, I.,Kovalev, K.,Gordeliy, V.I.,Shelaev, I.V.,Gostev, F.E.,Khakhulin, D.,Poddubnyy, V.V.,Gostev, T.S.,Cherepanov, D.A.,Polivka, T.,Kloz, M.,Friedrich, T.,Paschenko, V.Z.,Nadtochenko, V.A.,Rubin, A.B.,Kirpichnikov, M.P.
Role of hydrogen bond alternation and charge transfer states in photoactivation of the Orange Carotenoid Protein.
Commun Biol, 4:539-539, 2021

PubMed Abstract: Here, we propose a possible photoactivation mechanism of a 35-kDa blue light-triggered photoreceptor, the Orange Carotenoid Protein (OCP), suggesting that the reaction involves the transient formation of a protonated ketocarotenoid (oxocarbenium cation) state. Taking advantage of engineering an OCP variant carrying the Y201W mutation, which shows superior spectroscopic and structural properties, it is shown that the presence of Trp201 augments the impact of one critical H-bond between the ketocarotenoid and the protein. This confers an unprecedented homogeneity of the dark-adapted OCP state and substantially increases the yield of the excited photoproduct S*, which is important for the productive photocycle to proceed. A 1.37 Å crystal structure of OCP Y201W combined with femtosecond time-resolved absorption spectroscopy, kinetic analysis, and deconvolution of the spectral intermediates, as well as extensive quantum chemical calculations incorporating the effect of the local electric field, highlighted the role of charge-transfer states during OCP photoconversion.

PubMed: 33972665
DOI: 10.1038/s42003-021-02022-3

Experimental method

X-RAY DIFFRACTION (1.49 Å)