Multiplexing fluorescence and absorbance to monitor protein transport
They used a reporter system that consisted of a promoter that was sensitive to their protein of interest linked to GFP. In this way the could monitor the movement of their protein of interest across the membrane as well as metabolism of their protein of interest indirectly through changes in GFP expression. In order to normalize for cell number between the different mutants tested and over the 7 hour time course of their experiment they also used absorbance at 600 nm to measure cell turbidity. Just another way a multi-mode plate reader from BMG LABTECH can simplify your experiments!
The majority of the microplate readers that BMG LABTECH offers are multi-mode capable, including the PHERAstar FS and the new CLARIOstar, any one of which could perform similar analysis to serve your purposes.