Does anyone know if a Lys in close proximity to a Trp can cause
quenching ?
I've got a lysine lying along the indole ring of the
trp (the only one in the protein), with the NH3+ close to the
indole NH. When I unfold the protein, I see a large increase in
fluoresence as well as a redshift; the redshift I can understand,
the increase in fluoresence is the opposite to normal. There's no
other aromatics within 10A, and the trp is not solvent exposed.The lys
is part of a salt bridge with a glu and an asp.
Any suggestions ?
Ben Davis
MRC Unit for Protein Function and Design
Cambridge, UK
