Proline is one of the twenty amino acids that are used by living organisms as a building block of proteins. Technically, proline is an imino acid, as it contains no amino group.
In proteins, proline can act as a structural disruptor for α helices, and as a turning point in β sheets. Multiple prolines in a row can create a proline helix.
... which he would remain a member until his retirement in 1999 (he remains active within the nonviolence movement and regularly participates in WRL activities).
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