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Crambin (PDB: 1CRN)
A small protein whose experimentally determined atomic coordinates show a folded polypeptide. Look for the overall tertiary structure.
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If the embedded viewer is blocked by the browser or school network, use the full-view link above. An internet connection is required to retrieve the real molecular coordinates.AP Biology exploration prompts
- Locate alpha helices and beta sheets, where present. Which interactions stabilize these secondary structures?
- Explain how the sequence of amino acids (primary structure) influences the overall fold (tertiary structure).
- Compare ubiquitin with hemoglobin. What distinguishes tertiary from quaternary structure?
- Why might a change in pH or temperature disrupt a protein's structure and function?