7A- Myoglobin and Hemoglobin

Flashcards for key vocabulary and concepts related to myoglobin and hemoglobin discussed in the lecture.

Myoglobin

A protein that binds oxygen in muscle cells.

Heme Group

A complex of iron (Fe²⁺) contained in myoglobin and hemoglobin that binds oxygen.

Oxy-myoglobin

Myoglobin that is bound to oxygen (Fe(II) binding O2).

Histidine F8

An amino acid that interacts with the Fe(II) in myoglobin and hemoglobin.

Fractional Saturation (Y)

The fraction of binding sites occupied by ligand L relative to the total available sites.

Dissociation Constant (K)

A measure of the affinity between a ligand and its protein; determines how easily the ligand detaches.

pO2

Partial pressure of oxygen, a measure of oxygen concentration in blood.

Hemoglobin (Hb)

A protein that carries oxygen in the blood, consisting of four myoglobin-like subunits.

Cooperativity

The phenomenon where the binding of oxygen to one subunit of hemoglobin increases the affinity of other subunits for oxygen.

Allosteric Regulation

The regulation of a protein's function through the binding of a ligand to a site other than the active site.

T-state (Deoxy-Hb)

The low-affinity conformation of hemoglobin when it is not bound to oxygen.

R-state (Oxy-Hb)

The high-affinity conformation of hemoglobin when it is bound to oxygen.