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How two amino acids become one

Twenty amino acids form the basis of all proteins, but another two genetically encoded amino acids have also been discovered. The biosynthesis of one of these, pyrrolysine, has now been elucidated. See Letter p.647

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Figure 1: Proposed biosynthesis of pyrrolysine.


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Correspondence to Stephen W. Ragsdale.

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Ragsdale, S. How two amino acids become one. Nature 471, 583–584 (2011).

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