Glossary

BLOSUM62

BLOSUM62, given in detail below, is a commonly used scoring matrix in alignment problems considering protein strings. It assigns different alignment scores to substituted amino acids depending on the particular acids substituted; scores were computed based on the relative frequency of one amino acid to be substituted for another in a collection of known alignments.

The scoring matrix is "symmetric", which in this case means that the score assigned to substituting symbol $x$ for symbol $y$ is the same as that of substituting $y$ for $x$.

   A  C  D  E  F  G  H  I  K  L  M  N  P  Q  R  S  T  V  W  Y
A  4  0 -2 -1 -2  0 -2 -1 -1 -1 -1 -2 -1 -1 -1  1  0  0 -3 -2
C  0  9 -3 -4 -2 -3 -3 -1 -3 -1 -1 -3 -3 -3 -3 -1 -1 -1 -2 -2
D -2 -3  6  2 -3 -1 -1 -3 -1 -4 -3  1 -1  0 -2  0 -1 -3 -4 -3
E -1 -4  2  5 -3 -2  0 -3  1 -3 -2  0 -1  2  0  0 -1 -2 -3 -2
F -2 -2 -3 -3  6 -3 -1  0 -3  0  0 -3 -4 -3 -3 -2 -2 -1  1  3
G  0 -3 -1 -2 -3  6 -2 -4 -2 -4 -3  0 -2 -2 -2  0 -2 -3 -2 -3
H -2 -3 -1  0 -1 -2  8 -3 -1 -3 -2  1 -2  0  0 -1 -2 -3 -2  2
I -1 -1 -3 -3  0 -4 -3  4 -3  2  1 -3 -3 -3 -3 -2 -1  3 -3 -1
K -1 -3 -1  1 -3 -2 -1 -3  5 -2 -1  0 -1  1  2  0 -1 -2 -3 -2
L -1 -1 -4 -3  0 -4 -3  2 -2  4  2 -3 -3 -2 -2 -2 -1  1 -2 -1
M -1 -1 -3 -2  0 -3 -2  1 -1  2  5 -2 -2  0 -1 -1 -1  1 -1 -1
N -2 -3  1  0 -3  0  1 -3  0 -3 -2  6 -2  0  0  1  0 -3 -4 -2
P -1 -3 -1 -1 -4 -2 -2 -3 -1 -3 -2 -2  7 -1 -2 -1 -1 -2 -4 -3
Q -1 -3  0  2 -3 -2  0 -3  1 -2  0  0 -1  5  1  0 -1 -2 -2 -1
R -1 -3 -2  0 -3 -2  0 -3  2 -2 -1  0 -2  1  5 -1 -1 -3 -3 -2
S  1 -1  0  0 -2  0 -1 -2  0 -2 -1  1 -1  0 -1  4  1 -2 -3 -2
T  0 -1 -1 -1 -2 -2 -2 -1 -1 -1 -1  0 -1 -1 -1  1  5  0 -2 -2
V  0 -1 -3 -2 -1 -3 -3  3 -2  1  1 -3 -2 -2 -3 -2  0  4 -3 -1
W -3 -2 -4 -3  1 -2 -2 -3 -3 -2 -1 -4 -4 -2 -3 -3 -2 -3 11  2
Y -2 -2 -3 -2  3 -3  2 -1 -2 -1 -1 -2 -3 -1 -2 -2 -2 -1  2  7

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