AAToken 

The AAToken simple type is a restriction of AbstractSymbol 
that defines an IUPAC single character amino acid symbol.

Simple Type Information

Used By

Attributes AAPolymorphicStateSet/@symbol, AAState/@symbol, AAUncertainStateSet/@symbol

Source 

<xs:simpleType name="AAToken">
  <xs:annotation>
    <xs:documentation>The AAToken simple type is a restriction of AbstractSymbol that defines an IUPAC single character amino acid symbol.</xs:documentation>
  </xs:annotation>
  <xs:restriction base="AbstractSymbol">
    <xs:pattern value="[\*\-\?ABCDEFGHIKLMNPQRSTUVWXYZ]"/>
    <xs:length value="1"/>
  </xs:restriction>
</xs:simpleType>