The arrangements of amino acids into beta sheets give proteins their strength.

 

The Beta protein strands are often arranged in sheets. Most of the mutations in hemoglobin occur in the Beta strand.

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Sometimes the sheets are in barrels like this:

Note: The alpha/beta barrels are usually 8 beta sheets surrounded by 8 helixes.These are particularly interesting for us because the beta sheets have all of the radicals, their side chains, placed inside, making a hydrophobic core. Altogether it is a solid structure. The most active site is placed at the bottom of the barrel.

Look at the alpha helixes and beta sheets of hemoglobin.

Look at the beta sheets of antibodies.

Look more closely. What can we see inside alpha helixes and beta sheets?

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Protein Stories -+-Enzyme Stories -+- Index