Maybe low-spin, ferric cytochrome? 420 would be the soret peak
and 520 the alpha+beta peaks which are very broad in the
oxidized form. Add a little dithionite or ascorbate and see if
the soret peak shifts to longer wavelength and the alpha peak
sharpens up at 550-560 nm
Grishin, Andrey wrote:
D
Hi Andrey,
Are you sure it's not PLP? To me that looks like you have confounding
aggregation, and PLP in two forms, perhaps only partly incorporated when
considering your protein absorbance. Check out the spectra in the paper:
Turning pyridoxal-5'-phosphate-dependent enzymes into thermostable bin
Dear CCP4bb users,
this problem was already discussed many times here and I've read these
discussions before writing. I have a pale yellow protein. The spectrum contains
peaks at 320 and 420. Before we proceed to ICP-OES and wavelength scans at the
synchrotron, may be some of you had a similar
