Riemerella anatipestifer (RA) CH-1, a highly virulent field strain, was isolated and identified by our laboratory. The gldJ gene was conserved in RA, and it had a typical TATA promoter region and AU-rich sequence within the 5' untranslated region. The GldJ protein was an outer-membrane lipoprotein with a signal peptide cleavage site between amino acids 20 and 21. GldJ was also a member of proteins involved in gliding motility. The RA GldJ protein had 16 phosphorylation sites and 4 N-glycosylation sites. These functional sites played an important role in the posttranslational modification of the GldJ protein. In addition, the GldJ protein of RA CH-1 had strong immunogenicity. Fifteen B-cell epitopes were identified in the GldJ protein, which might be a good biological material for the development of a subunit vaccine and diagnostic reagents.