Validation of 16S rRNA and Complete rpoB Gene Sequence Analysis for the Identification of Elizabethkingia Species.

Bacteria in the genus have emerged as a cause of life-threatening infections in humans. However, accurate species identification of these pathogens relies on molecular techniques. We aimed to evaluate the accuracy of 16S rRNA and complete RNA polymerase β-subunit () gene sequences in identifying species. A total of 173 strains with whole-genome sequences in GenBank were included. The 16S rRNA gene and rpoB gene sequences from the same strains were examined. Of the 41 strains, all exhibited >99.5% 16S rRNA similarity to its type strain. Only 83% of the 99 strains shared >99.5% 16S rRNA gene similarity with its type strain. All strains of and formed a cluster distinct from the other species in the 16S rRNA and gene phylogenetic trees. The polymorphisms of 16S rRNA gene sequences are not sufficient for constructing a phylogenetic tree to discriminate species in the cluster (, , , and ). The complete gene phylogenetic tree clearly delineates all strains of species. The complete gene sequencing could be a useful complementary phylogenetic marker for the accurate identification of species.