3GB3

X-ray structure of genetically encoded photosensitizer KillerRed in native form

Summary for 3GB3

• Entry DOI: 10.2210/pdb3gb3/pdb
• Descriptor: KillerRed, SULFATE ION (3 entities in total)
• Functional Keywords: fluorescent protein, genetically encoded photosensitizer, killerred, phototoxicity
• Biological source: Anthomedusae sp. DC-2005
• Total number of polymer chains: 2
• Total formula weight: 53211.68

Authors

Pletnev, S.,Pletneva, N.V.,Pletnev, V.Z. (deposition date: 2009-02-18, release date: 2009-09-08, Last modification date: 2024-10-09)

Primary citation

Pletnev, S.,Gurskaya, N.G.,Pletneva, N.V.,Lukyanov, K.A.,Chudakov, D.M.,Martynov, V.I.,Popov, V.O.,Kovalchuk, M.V.,Wlodawer, A.,Dauter, Z.,Pletnev, V.
Structural basis for phototoxicity of the genetically encoded photosensitizer KillerRed.
J.Biol.Chem., 284:32028-32039, 2009

PubMed Abstract: KillerRed is the only known fluorescent protein that demonstrates notable phototoxicity, exceeding that of the other green and red fluorescent proteins by at least 1,000-fold. KillerRed could serve as an instrument to inactivate target proteins or to kill cell populations in photodynamic therapy. However, the nature of KillerRed phototoxicity has remained unclear, impeding the development of more phototoxic variants. Here we present the results of a high resolution crystallographic study of KillerRed in the active fluorescent and in the photobleached non-fluorescent states. A unique and striking feature of the structure is a water-filled channel reaching the chromophore area from the end cap of the beta-barrel that is probably one of the key structural features responsible for phototoxicity. A study of the structure-function relationship of KillerRed, supported by structure-based, site-directed mutagenesis, has also revealed the key residues most likely responsible for the phototoxic effect. In particular, Glu(68) and Ser(119), located adjacent to the chromophore, have been assigned as the primary trigger of the reaction chain.

PubMed: 19737938
DOI: 10.1074/jbc.M109.054973

Experimental method

X-RAY DIFFRACTION (1.75 Å)