In the naturally occurring variant hemoglobin Rainier, Tyr145? is replaced with a Cys. This mutation allows for disulfide bond formation with a nearby Cys in the same subunit.

a. By examining the structure of hemoglobin (Pdb file = 1HGA), suggestwhich Cys makes this new disulfide.

b. Formation of this disulfide prevents the formation of some of theion pairs found exclusively in the T-state. Does hemoglobin Rainierbind oxygen more or less tightly than normal hemoglobin?

c. Does hemoglobin Rainier bind have a greater or lesser Bohr effectthan normal hemoglobin.