              Chemical sequence expressed as string of one-letter \
               amino acid codes. \
\
A  for alanine or adenine\
B  for ambiguous asparagine/aspartic-acid\
R  for arginine\
N  for asparagine\
D  for aspartic-acid\
C  for cysteine or cystine or cytosine\
Q  for glutamine\
E  for glutamic-acid\
Z  for ambiguous glutamine/glutamic acid\
G  for glycine or guanine\
H  for histidine\
I  for isoleucine\
L  for leucine\
K  for lysine\
M  for methionine\
F  for phenylalanine\
P  for proline\
S  for serine\
T  for threonine or thymine\
W  for tryptophan\
Y  for tyrosine\
V  for valine\
U  for uracil