The application of riboswitch sequencing for human gut bacterial classification and identification

Yaoyao Wu¹, Deying Zhang^1,2, Anqi Duan, Yaqi Ao, Sanshu Li

Medical School, Engineering Research Center of Molecular Medicine of Ministry of Education, Key Laboratory of Precision Medicine and Molecular Diagnosis of Fujian Universities, Institute of Genomics, School of Biomedical Sciences, Huaqiao University, Xiamen 361021, PR China.

Bacteria, especially gut bacteria play important roles in human health and diseases. The classification of many bacterial genera by the 16S ribosomal RNA (rRNA) has failed due to its low inter-species resolution. Given the wide distribution of riboswitches in bacteria, they may help 16S rRNA differentiate closely related species. We found that among 28 groups of species that could not be distinguished by 16S rRNA, eight of them could be separated by the TPP riboswitch and other riboswitches. Moreover, the species in the 16S rRNA database and these riboswitch databases overlap, therefore, using riboswitch databases can help 16S rRNA better identify species. In addition, we used Klenow DNA polymerase and a pair of short primers to facilitate the library construction of TPP riboswitches for sequencing. The sequencing results showed that the TPP riboswitch could detect the major phyla similar to those detected by 16S rRNA. Therefore, the TPP riboswitch and other riboswitch classes could potentially be applied to gut bacteria classification.