Hemoglobin and Cyanide
Sean M. Decatur
sdecatur at mhc.mtholyoke.edu
Fri Dec 8 16:23:52 EST 1995
Bob_Hoesch at fws.gov (Bob Hoesch) wrote:
>This makes sense in terms of a change in the number of spectrophotometric
>absorption peaks, but I still don't think we have a good explanation for the
>reduction in the number of electrophoretic bands. After all, the protein
>doesn't go away.
Heres a thought--
When CN- binds to metHb, the net charge of the protein is the same as deoxy- or oxyHb, whereas metHb (with H2O bound) has net charge of +1 relative to the reduced (oxy- and dexoy-) species. Thus, if there is a mixture of reduced and oxidized irons present in the Hb solution, there will be a mixture of pIs (and presumably multiple IEF bands). However, when CN- is added the metHbCN will have the same net charge as the oxyHb and/or deoxyHb, so the Hbs should all have the same pI.
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