Sandbox 206: Difference between revisions

Yellow Fluorescent protein (YFP) is a variant of Green fluorescent protein (GFP). This protein is very useful like a biomarker in a lot of biological applications. First, the GFP was mutated In YFP. But the YFP had a low fluorescence because of a slow maturation and it was very sensitive to experimental condition (pH, Cl-). To increase the brightness of the protein, maturation speed and other properties, five mutations were done to obtain Venus, a Yellow Fluorescent Protein less sensitive to experimental condition. <ref> Crystal Structure of Venus, a Yellow Fluorescent Protein with Improved Maturation and Reduced Environmental Sensitivity Rekas, A., Alattia, J.R., Nagai, T., Miyawaki, A., and Ikura M., 2002 Pubmed : [http://www.ncbi.nlm.nih.gov/pubmed/12370172?dopt=Abstract 12370172] DOI : [http://www.jbc.org/content/277/52/50573 10.1074/jbc.M209524200] Disponible on [http://www.ebi.ac.uk/pdbe-srv/view/entry/1myw/citation.html]</ref>

Venus is a 27 kDa protein (26 875,50Da) consisting of 239 residues and form a secondary structure of 7 <scene name='Sandbox_206/Alpha_helix/1'>α-helix</scene> (2 in the center of the molecule) and 11 <scene name='Sandbox_206/Sheet/2'> β-sheet</scene>. This molecule is monomeric. Venus has many common point with the GFP and also with the EYFP. In all three structures compared, the cross-section taken perpendicularly to the long axis of the barrel is not perfectly circular but rather <scene name='Sandbox_206/Oval/1'>oval</scene> in shape. While the longer diameter of the oval cross-section of all three proteins is identical (23.8 Å measured from distances of four Cα pairs), the shorter diameter differs between EYFP (22.3 Å) and Venus (21.9 Å). The difference in the oval shape between these yellow variants is closely related to the packing of inte- rior amino acid residues and influences the integrity of dimer interface.