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"Turn-on" protein fluorescence: in situ formation of cyanine dyes.

ABSTRACT: Protein reengineering of cellular retinoic acid binding protein II (CRABPII) has yielded a genetically addressable system, capable of binding a profluorophoric chromophore that results in fluorescent protein/chromophore complexes. These complexes exhibit far-red emission, with high quantum efficiencies and brightness and also exhibit excellent pH stability spanning the range of 2-11. In the course of this study, it became evident that single mutations of L121E and R59W were most effective in improving the fluorescent characteristics of CRABPII mutants as well as the kinetics of complex formation. The readily crystallizable nature of these proteins was invaluable to provide clues for the observed spectroscopic behavior that results from single mutation of key residues.

SUBMITTER: Yapici I

PROVIDER: S-EPMC4311949 | biostudies-other | 2015 Jan

REPOSITORIES: biostudies-other

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"Turn-on" protein fluorescence: in situ formation of cyanine dyes.

Yapici Ipek I Lee Kin Sing Stephen KS Berbasova Tetyana T Nosrati Meisam M Jia Xiaofei X Vasileiou Chrysoula C Wang Wenjing W Santos Elizabeth M EM Geiger James H JH Borhan Babak B

Journal of the American Chemical Society 20150114 3

Protein reengineering of cellular retinoic acid binding protein II (CRABPII) has yielded a genetically addressable system, capable of binding a profluorophoric chromophore that results in fluorescent protein/chromophore complexes. These complexes exhibit far-red emission, with high quantum efficiencies and brightness and also exhibit excellent pH stability spanning the range of 2-11. In the course of this study, it became evident that single mutations of L121E and R59W were most effective in imp ...[more]

PMID: 25534273

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