Jan,
Crystals containing haem protein are not necessarily red, the colour
depends on the oxidation state of the haem and on the haem/protein
ratio. A FeIII haem will look yellowish, gold or brown depending on
the haem/protein ratio, while an FeII haem will look more pink or red.
Daniel
Ian Ollmann a écrit :
On Mar 12, 2008, at 12:48 PM, Jan Schoepe wrote:
Hello everybody,
I wonder if anybody has experience with heme (or to be more precise:
heme b) containing proteins which Xtals do not look red under the
microscope. How might the technique for crystallization (e.g. sitting
drop, hanging drop) influence the intensity of the color? Many thanks!
If there is no metal in the heme, its color will be very different. If
your crystallization buffer contains EDTA or other strong chelating
agents, I imagine this might happen, though protein crystallization is
not my area.
Ian
