O51 antigen prediction issues and 35|O51 wzx allele in SISTR v1.1.1 database

[kbessonov1984]

In SISTR v1.1.1. the O51 antigen prediction might be jeopardized as confirmed by recent PulseNet submission. The SISTR v1.1.1 in-silico prediction provided IIIb 51:k:z35 while traditional serotyping predicted IIIb 47:k:z35 serovar. SISTR used O51|35 allele for the wzx gene which is ~600 nt and might be truncated as other O51 alleles are of 1220 bp size. In addition, BLAST of this allele identified the top 100% id hit mapping to 47:k:35 serovar with ACCESSION CP053583.1. Removal of this problematic O51|35 allele had resulted in correct in-silico SISTR v1.1.1 serovar prediction (47:k:z35)

Will need to fix this issue in the SISTR database in the next release and run tests against the validation panel again in the Q1 of 2022.