title: An enhanced monomeric blue fluorescent protein with the high chemical stability of the chromophore.
abstract: Commonly used monomeric blue fluorescent proteins suffer from moderate brightness. The brightest of them, mTagBFP, has a notably low chemical stability over time. Prolonged incubation of mTagBFP leads to its transition from a blue fluorescent state with absorbance at 401 nm to a non-fluorescent state with absorbance at 330 nm. Here, we have determined the chemical structure of the degraded product of the blue mTagBFP-like chromophore. On the basis of mTagBFP we have developed an improved variant, named mTagBFP2. mTagBFP2 exhibits 2-fold greater chemical stability and substantially higher brightness in live cells than mTagBFP. mTagBFP2 is also 1.2-fold and 1.7-fold more photostable than mTagBFP in widefield and confocal microscopy setups, respectively. mTagBFP2 maintains all other beneficial properties of the parental mTagBFP including the high pH stability and fast chromophore formation. The enhanced photostability and chromophore chemical stability of mTagBFP2 make it a superior protein tag. mTagBFP2 performs well in the numerous protein fusions and surpasses mTagBFP as a donor in Förster resonance energy transfer with several green fluorescent protein acceptors.
authors.affiliation: Department of Anatomy and Structural Biology, and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, New York, New York, United States of America.
authors.forename: Oksana M
authors.initials: OM
authors.lastname: Subach
authors.forename: Paula J
authors.initials: PJ
authors.lastname: Cranfill
authors.forename: Michael W
authors.initials: MW
authors.lastname: Davidson
authors.forename: Vladislav V
authors.initials: VV
authors.lastname: Verkhusha
mesh_terms: D002384:Catalysis; D002470:Cell Survival; D005453:Fluorescence; D031541:Fluorescence Resonance Energy Transfer; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D055668:Photochemical Processes; D055550:Protein Stability; D011993:Recombinant Fusion Proteins / Q000378:metabolism
chemical_list: D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins