Juggling with fluorescent proteins: Spectrum and structural changes of the mCardinal2 variants

• DOI: 10.1016/j.bbrc.2022.01.044
• Publication Date: 2022-01-14T01:06:39Z
• Authors: Tae-Yeon Kim; Tae-Sung Yoon; Sunghyun Kang; Muhammad Afzal
• Keywords: Cyan; Chromophore; Blueshift; Red shift

mCardinal2 is a red fluorescent protein developed through the designs of mKate, mNeptune and mCardinal. Fluorescence spectrums its five mutants (T143C, T143G, C158A, C158D M160E) were measured with their quantum yields. C158A increased brightness slight changes in fluorescence while T143C, T143G M160E decreased blue shift spectrums, which resulted green, cyan green proteins respectively. Crystal structures all six variants analyzed compared together those LSS-mKate1, LSS-mKate2 Around Cα-Cβ bond Tyr64 MYG chromophores, only trans conformation others mostly cis conformation. Blue-shift brightness-decreased showed diminished hydrogen bonds large-Stoke-shift brightness-increased variant enhanced around chromophore.