From: Prediction of protein-RNA residue-base contacts using two-dimensional conditional random field with the lasso
# groups
classification of amino acids
2
MLVICGATSPFYW/DENQRKH
4
MLVIC/GATSP/FYW/DENQRKH
8
MLVIC/GA/TS/P/FYW/DENQ/RK/H
10
MLVI/C/G/A/TS/P/FYW/DENQ/RK/H
15
MLVI/C/G/A/T/S/P/FY/W/D/E/N/Q/RK/H