BCH210H1 Chapter Notes -Partial Pressure, Histidine, Protoporphyrin Ix
49
BCH210H1 Full Course Notes
Verified Note
49 documents
Document Summary
Myoglobinis a relatively small monomeric protein that facilitates the diffusion of oxygen in vertebrates. Responsible for supplying oxygen to muscle tissue in reptiles, birds, and mammals. Hemoglobin is a larger tetrameric protein that carries oxygen in blood. Both myoglobin and hemoglobin contains a heme prosthetic group. *prosthetic group is a protein-bound organic molecule essential for the activity of the protein. Heme consists of a tetrapyrrole ring system (protoporphyrin ix) complexed with iron. The four rings of this system are linked by methene (-ch=) bridges. The unsaturated porphyrin is highly conjugated (joined) and planar. The iron of heme group is a ferrous iron (fe2+) which is caged inside the porphyrin ring. This form a complex with up ligands around iron can ferrous to 6 it when myoglobin/hemoglobin is oxygenated and usually with 5 ligands when in deoxygenated form: The coordinated nitrogen atoms help prevent conversion of the heme iron to the ferric.
