The role of local and remote amino acid substitutions for optimizing fluorescence in bacteriophytochromes: A case study on iRFP.

ABSTRACT: Bacteriophytochromes are promising tools for tissue microscopy and imaging due to their fluorescence in the near-infrared region. These applications require optimization of the originally low fluorescence quantum yields via genetic engineering. Factors that favour fluorescence over other non-radiative excited state decay channels are yet poorly understood. In this work we employed resonance Raman and fluorescence spectroscopy to analyse the consequences of multiple amino acid substitutions on fluorescence of the iRFP713 benchmark protein. Two groups of mutations distinguishing iRFP from its precursor, the PAS-GAF domain of the bacteriophytochrome P2 from Rhodopseudomonas palustris, have qualitatively different effects on the biliverdin cofactor, which exists in a fluorescent (state II) and

SUBMITTER: Buhrke D 

PROVIDER: S-EPMC4916461 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature