Advantages of substituting bioluminescence for fluorescence in a resonance energy transfer-based periplasmic binding protein biosensor

► A BRET2-based maltose biosensor was constructed using genetically encoded components. ► MBP was flanked by green fluorescent protein (GFP2) and Renilla luciferase variant (RLuc2). ► BRET2 was three times more sensitive than FRET for measuring maltose. ► The EC50 was 0.37 μM for maltose and the BRET2 response was linear over three orders of magnitude. ► Maltose was accurately measured in beer demonstrating potential use in the fermentation industry.