Variants of DsRed fluorescent protein: Development of a copper sensor.
The fluorescence quenching of drFP583 (DsRed) protein by metal ions was investigated. CuSO4 reversibly and pH dependently quenched the red emission at 583 nm of drFP583. The copper binding constant was 15 mM. Following random mutagenesis, blue- and red-shifted mutants of drFP583 were generated, and their metal sensing properties were examined. Mutant gRF possessed properties similar to green fluorescent protein and had a 18 mM copper binding constant. Mutant Rmu162 had an extraordinary red-shifted emission peak at 620 nm. A third mutant, Rmu13, had dual emission peaks at 500 nm and 583 nm and possessed the properties of a copper sensor with a binding constant of 11 mM.
Eli
Pharhad
P
Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5G 1L7, Canada.
Chakrabartty
Avijit
A
D015374:Biosensing Techniques / Q000379:methods*; D003300:Copper / Q000032:analysis*; D019327:Copper Sulfate; D006863:Hydrogen-Ion Concentration; D008164:Luminescent Proteins / Q000235:genetics*; D016296:Mutagenesis; D011485:Protein Binding; D013050:Spectrometry, Fluorescence
D008164:Luminescent Proteins; C413663:fluorescent protein 583; D003300:Copper; D019327:Copper Sulfate