Molecule of the Month: Myoglobin
Myoglobin was the first protein to have its atomic structure determined, revealing how it stores oxygen in muscle cells.
The First Protein Structure
Myoglobin and Muscles
Visualizing Protein Structure
Myoglobin and Whales
Oxygen Bound to Myoglobin
Exploring the Structure
Structural Features of Myoglobin (PDB entry 1mbn)
The atomic structure of myoglobin revealed many of the basic principles of protein structure and stability. For instance, the structure showed that when the protein chain folds into a globular structure, carbon-rich amino acids are sheltered inside and charged amino acids are most often found on the surface, occasionally forming salt bridges that pair two opposite charges (shown here with circles). To explore some of these principles, click on the image for an interactive JSmol.
Topics for Further Discussion
- You can use the sequence comparison tool to align the sequences of different myoglobins, looking for mutations. For instance, here is the alignment of whale and pig myoglobin used to create the illustration in this column.
- PDB entry 2jho includes myoglobin poisoned by cyanide. Take a look and you'll see that the cyanide blocks the binding site for oxygen.
January 2000, David Goodselldoi:10.2210/rcsb_pdb/mom_2000_1