Flavin Mononucleotide-binding fluorescent proteins

Flavin mononucleotide (FMN)-binding fluorescent proteins (FbFPs) are novel reporters for cell microscopy, outperforming green fluorescent proteins (GFP) and derivatives in anaerobic or microaerobic environments (Figure 1). Furthermore they are better suited for incorporation into small-sized genomes and for following viral infections, protein expression and protein maturation in real-time (figure 2, 3). FbFPs are derived from photoreceptors of the LOV (Light, Oxygen Voltage) superfamily and exhibit fluorescence in the green region of the spectrum with quantum yield of ca. 0.2-0.3. FbFPs have been introduced as fluorescent reporters in 2007 and have been ever since exploited for a number of selected applications, including real-time biosensing of changing oxygen level within living cells.