DsRED structure

Gross, L. A. (2000). The structure of the chromophore within DsRed a red fluorescent protein from coral. Proc. Natl. Acad. Sci. USA 22 11990-11995. 

Yarbrough D, Wachter RM, Kallio K, Matz MV, Remington SJ (2001) Refined crystal structure of DsRed, a red fluorescent protein from coral, at 2.0-A resolution. Proc Natl Acad Sci USA 98 462 167... 

Wall MA, Socolich M, Ranganathan R (2000) The structural basis for red fluorescence in the tetrameric GFP homolog DsRed. Nat Stmct Biol 7 1133-1138... 

Remarkably, although there is little sequence homology between the members of the GFP super family (DsRed and avGFP share less then 30% sequence homology), their crystal structures are highly similar [25-28]. The /l-barrel structure is a feature common to all members of the GFP super family for which the crystal structure has been solved. However, whereas avGFP is present mainly as a monomer, many other VFPs form obligate di- or tetramers. 

DsRed (Fig. 5.3E) is a bright RFP with excitation and emission maxima at 558 and 583 nm, respectively. Despite the bright red fluorescence, application of DsRed has been restricted, because of slow and inefficient maturation and its tetrameric structure [70, 71], The poor maturation efficiency has been overcome by random mutagenesis, which resulted in the fast maturing variant DsRedTl [72]. However, DsRedTl remains tetrameric. 

Hsiao YW, Sanchez-Garcia E, Doerr M, Thiel W (2010) Quantum refinement of protein structures implementation and application to the red fluorescent protein DsRed.Ml. J Phys ChemB 114 15413-15423... 

However, during the last decade a number of GFP mutants were described showing altered spectral properties and/or improved solubility upon expression in heterologous systems. In addition, numerous other naturally occurring fluorescent proteins were described such as the red-fluorescent protein from Discosoma sp. (DsRED). A comprehensive description of the available fluorescent proteins is given including the spectral properties, amino-acid sequence alignments, comparisons of the secondary and tertiary structures of the proteins. 

About one year after its first description the three dimensional structure of DsRED and chemical structure of the its chromophore was described by two independent groups [25, 26]. The structural data and other experimental evidences proved that the DsRED protein is an obligate tetramer and that the chromophore is GFP-like but possesses an extended 7i-electron system due to an additional oxidation step [27,28]. 

Fig. 2 Sdiematk of folding, chromophore formation, and chromophore modification of DsRed. The p-can structure represents the native conformation of the protein, while the denatured form is shown as an irregular chain. It is not known at which step oligomerization occurs, n-con-jugation for visible-light absorption is indicated in gray. Reprinted with permission from Miyawaki et al., Curr. Opin. Chem. Biol. 7,560 (2003). Copyright 2003 Elsevier...

Until recently, the green fluorescent protein (avGFP) from the jellyfish Aequorea victoria was the only fluorescent protein to be widely mutated and altered for biological apphcations. Meanwhile, a family of GFP-like proteins from different organisms has emerged that share the common fl-barrel fold structure and intrinsic chromophores but represent a vast spectral range, with (E)GFP and DsRed being the most prominent representatives [33]. 

A new red protein eqFP611 from Entacmaea quadricolor displayed both monomeric and tetrameric features in initial studies [78]. FCS analysis at low nmol/1 concentrations predicted a mass ratio of 2.7 between DsRed and eqFP611 and produced a diffusion coefficient similar to the monomeric GFP mutant Citrine. In contrast, size-exclusion chromatography and the recently resolved crystal structure of eqFP611 indicated that eqFP611 too can form tetramers... 

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