Microbial Identification Kits and Libraries

The target for bacterial identification is the 16S ribosomal RNA (rRNA) gene sequence. The 16S rRNA is ubiquitous and can therefore be used to study phylogenetic relationships among all bacteria. The gene is 1,500 base pairs (bp) long and contains 9 variable regions. The conserved regions are identical in all micro-organisms and can be used for amplification via PCR, while the divergent regions are used for identification through sequencing. 

With the MicroSEQ ID method, users have the option of choosing to sequence the first 500 bp of the 16S rDNA gene or the full 1,500 bp. Kits and the supporting validated library databases are available for both options. The first 500 bp are sufficient for a routine identification that encompasses 3 of the 9 hypervariable regions of the 16S gene (Figure 1). In some cases, the 500 bp region is not enough to discriminate among very closely related bacteria and therefore requires a more informative full gene read. Furthermore, sequencing of the entire 1,500 bp sequence is required when describing a new species.

Figure 1. Hypervariable regions within the 16S rRNA gene. There are 9 hypervariable regions within the bacterial 16S gene, indicated in green. The conserved regions are indicated in grey.