Name:

Kd

Category:

Binding

Property:

Dissociation Constant (Kd)

Units:

nM (nanoMolar)

Measurement Technique:

Surface Plasmon Resonance (SPR)

Buffers:

None

Temperature:

None

pH:

None

Protein Concentration:

None

Wavelength:

None

Ionic Strength:

None

Details:

Surface plasmon resonance utilizing a ProteOn XPR36 (BioRad) was employed to determine the binding of each mutant to surface-immobilized SEB antigen. All SPR measurements were done at least in duplicate, often with several different preparations of each mutant as a monomer. The KD determined by SPR for replicates agreed within at least a factor of 3. Other than the mutants at P55, the KD values were considered to be essentially equivalent to wild-type, as KD determinations can be problematic when off rates are so slow.