title: Blue fluorescent protein derived from the mutated purple chromoprotein isolated from the sea anemone Stichodactyla haddoni.
abstract: Chromoproteins, especially far-red fluorescent proteins with long stokes shift, are good sources for engineering biological research tools. However, chromoproteins have not been used for developing fluorescent proteins with short emission wavelength. Therefore, we herein report the development of a blue fluorescent protein, termed shBFP, which is derived from a purple chromoprotein isolated from the sea anemone Stichodacyla haddoni (shCP) after shCP was simultaneously mutated on E63L and Y64L. The shBFP chromophore is composed of Leu-Leu-Gly, which introduced a maximum excitation and emission wavelength at 401 nm and 458 nm, respectively, and a quantum yield of 0.79. Interestingly, the N158S and L173I double mutations of shBFP conducted in the chromophore environment further shifted the maximum excitation to 375 nm, and elevated the quantum yield to 0.84. Thus, shBFP, which is based on the Leu-Leu-Gly chromophore composition, results in higher quantum yields and short wavelength emission. Additionally, we found that the cDNA of shBFP is stably expressed in zebrafish embryos with fidelity, indicating the application of shBFP as a biomarker or selective marker.
authors: Institute of Molecular and Cellular Biology, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei106, Taiwan.
authors: Cheng-Yi
authors: CY
authors: Chiang
authors: Institute of Biomedical Sciences, MacKay Medical College, No. 46, Section 3, Zhongzhen Road, Sanzhi Dist., New Taipei City252, Taiwan.
authors: Cheng-Yung
authors: CY
authors: Lin
authors: Institute of Molecular and Cellular Biology, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei106, Taiwan.
authors: Yen-Ting
authors: YT
authors: Chen
authors: Institute of Biomedical Sciences, MacKay Medical College, No. 46, Section 3, Zhongzhen Road, Sanzhi Dist., New Taipei City252, Taiwan.
authors: Huai-Jen
authors: HJ
authors: Tsai
keywords: biomarker; blue fluorescent protein; genetic engineering; protein engineering; transgenesis