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Name: Steven
Status: Student
Grade:  Other
Location: Outside U.S.
Country: Greece
Date: Spring 2010

Are there more than 20 amino acids on earth?


Twenty-two amino acids are naturally incorporated into polypeptides and are called proteinogenic or standard amino acids.

Aside from the twenty-two standard amino acids, there are also a vast number of "non-standard" amino acids.

Please see the following URL for full coverage of this question.

Sincere regards,
Mike Stewart

Yes, but only 20 that are commonly occurring in proteins.

Ron Baker, Ph.D.



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