/usr/share/genometools/gtdata/trans/TransMass is in genometools-common 1.5.1-2ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | # 24-character amino acid alphabet in upper case
# in addition to the usual 20 aminoacids, we have the following
# B O X Z
G
A
S
P
V
T
C
LIX
N
O
B
D
Q
K
Z
E
M
H
F
R
Y
W
*
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