Counted 19 for sp_0005_SySynthetic ConstructTumor protein p53 N-t ..
sp_0005_SySynthetic ConstructTumor protein p53 N-terminal transcription-activation domain
A=9 C=2 D=3 E=4 F=2 G=15 I=3 K=3 L=9 M=3 N=5 P=2 Q=10 R=8 S=12 T=6 V=8 W=1 Y=5
Amino acid alphabet = 19

Sequence length = 124
Counted 20 for sp_0017_CaCamelidSorghum bicolor multidrug and tox ..
sp_0017_CaCamelidSorghum bicolor multidrug and toxic compound extrusion sbmate
A=10 C=2 D=4 E=4 F=2 G=15 H=1 I=2 K=4 L=7 M=2 N=5 P=3 Q=6 R=4 S=18 T=7 V=10 W=5 Y=10
Amino acid alphabet = 20

Sequence length = 143
Least number of amino acids is 19 in these entries
sp_0005_SySynthetic ConstructTumor protein p53 N-terminal transcription-activation domain

All results in ascending count
19  sp_0005_SySynthetic ConstructTumor protein p53 N-terminal transcription-activation domain
20  sp_0017_CaCamelidSorghum bicolor multidrug and toxic compound extrusion sbmate

Exclusion of various amino acids is as follows
B=2
H=1
J=2
O=2
U=2
X=2
Z=2