Bacterial DNA barcode sequence identification [BDNA]
Published: July 8th, 2009
Revised: February 23rd, 2023
This test provides a low-level identification of a single bacterial isolate by sequencing of portions of the 16S ribosomal small subunit gene region. DNA-based sequence identification is the gold-standard for microbial identification, since it is capable of identifying rare or atypical isolates of bacteria irrespective of their responses to diagnostic culture media or biochemical tests.
DNA is isolated from cells using standard procedures. A diagnostic portion of the ribosomal small subunit gene is amplified by PCR and sequenced in both directions. A consensus sequence of both forward and reverse strands is constructed, and this sequence is used to query the Ribosomal Database Project (RDP), an online data analysis and alignment tool consisting of annotated Bacterial and Archaeal small-subunit 16S rRNA sequences. This approach to bacteria identification is unmatched in its ability to accurately identify troublesome isolates, or to ascertain the taxonomic position of novel strains.