title: Far-red fluorescent proteins evolved from a blue chromoprotein from Actinia equina.
abstract: Proteins of the GFP (green fluorescent protein) family demonstrate a great spectral and phylogenetic diversity. However, there is still an intense demand for red-shifted GFP-like proteins in both basic and applied science. To obtain GFP-like chromoproteins with red-shifted absorption, we performed a broad search in blue-coloured Anthozoa species. We revealed specimens of Actinia equina (beadlet anemone) exhibiting a bright blue circle band at the edge of the basal disc. A novel blue chromoprotein, aeCP597, with an absorption maximum at 597 nm determining the coloration of the anemone basal disk was cloned. AeCP597 carries a chromophore chemically identical with that of the well-studied DsRed (red fluorescent protein from Discosoma sp.). Thus a strong 42-nm bathochromic shift of aeCP597 absorption compared with DsRed is determined by peculiarities of chromophore environment. Site-directed and random mutagenesis of aeCP597 resulted in far-red fluorescent mutants with emission maxima at up to 663 nm. The most bright and stable mutant AQ143 possessed excitation and emission maxima at 595 and 655 nm respectively. Thus aeCP597 and its fluorescent mutants set a new record of red-shifted absorption and emission maxima among GFP-like proteins.
authors.affiliation: Shemiakin-Ovchinnikov Institute of Bioorganic Chemistry, Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Shkrob
authors.forename: Yurii G
authors.initials: YG
authors.lastname: Yanushevich
authors.forename: Dmitriy M
authors.initials: DM
authors.lastname: Chudakov
authors.forename: Nadya G
authors.initials: NG
authors.lastname: Gurskaya
authors.forename: Yulii A
authors.initials: YA
authors.lastname: Labas
authors.forename: Sergey Y
authors.initials: SY
authors.lastname: Poponov
authors.forename: Nikolay N
authors.initials: NN
authors.lastname: Mudrik
authors.forename: Sergey
authors.initials: S
authors.lastname: Lukyanov
authors.forename: Konstantin A
authors.initials: KA
authors.lastname: Lukyanov
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D037421:Anthozoa / Q000378:metabolism*; D003001:Cloning, Molecular; D003116:Color; D004926:Escherichia coli; D019143:Evolution, Molecular; D015870:Gene Expression; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D008164:Luminescent Proteins