restypes_with_x

List of amino acids including 'UNK'. 'UNK' means unknown amino acid and is represented by 'X'. Totally (20 + 1) types of amino acid are in the list.

value:

['A', 'R', 'N', 'D', 'C', 'Q', 'E', 'G', 'H', 'I', 'L', 'K', 'M', 'F', 'P', 'S', 'T', 'W', 'Y', 'V', 'X']