Scoring matrix properties

Matrix gap1
penalty
%
identity
bits /
pos.
random
aln. len.
50 bit
length

SSEARCH 36.3.6
BLOSUM502 10/2 25.3 0.21 160 238
BLOSUM62 11/1 28.9 0.40 86 125
VTML 1602 12/2 23.9 0.25 139 200
VTML 140 10/1 28.4 0.44 82 114
VTML 120 11/1 32.1 0.54 62 93
VTML 80 10/1 40.5 0.74 47 68
VTML 40 13/1 64.7 1.92 18 26
VTML 20 15/2 86.1 3.30 11 15
VTML 10 16/2 90.9 3.87 9 13

BLAST 2.2.27+
BLOSUM452 13/2 29.4 0.39 85 128
BLOSUM62 11/1 29.6 0.41 82 122
BLOSUM80 10/1 32.0 0.48 69 104
PAM70 10/1 33.9 0.58 56 86
PAM30 9/1 45.9 0.90 34 56

1 Gap open/extend penalty, where the total penalty is open + r * extend, where r is the number of residues in the gap. Thus, a 10/2 penalty produces a penalty of 12 for a one residue gap, 14 for two residues, etc.

2 Scaled in 1/3-bit units; all other matrices are scaled in 1/2-bit units.