Question

The pKa of the GFP is around a pH of 6. Protonated GFP is not fluorescent at a wavelength of 488 nm. Would you expect GFP to fluoresce at physiological pH of 7? Would you expect GFP to fluoresce in the lysosome of cells? Justify your answer

Answer 1

to be protonated, the GFP needs to be in more acidic medium and as it is mentioned here that the pka of gfp is at 6ph, therefore, at the ph 7 the gfp is not protonated and thus it will flouorece as it is mentioned in the question that the protonated gfp wont fluorescent but a non protonated will. therefore, at the ph 7 the gfp will fluoresce .

while in the lysosomal cells, the medium is way too much acidic and thus, in acidic medium the gfp will get protonated, as in lysosome the ph is less than 6 , and therefore gfp will get protonated and thus will fluoresce.