Identification and functional validation of kynureninases from oral bacteria
2
Issued Date
2025-01-01
Resource Type
eISSN
20002297
Scopus ID
2-s2.0-105017092400
Journal Title
Journal of Oral Microbiology
Volume
17
Issue
1
Rights Holder(s)
SCOPUS
Bibliographic Citation
Journal of Oral Microbiology Vol.17 No.1 (2025)
Suggested Citation
Charoenwongwatthana P., Ahmed H., Charlton A., Gidley M.D., Telezhkin V., Coulter J., Chang C.Y. Identification and functional validation of kynureninases from oral bacteria. Journal of Oral Microbiology Vol.17 No.1 (2025). doi:10.1080/20002297.2025.2561213 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/112399
Title
Identification and functional validation of kynureninases from oral bacteria
Corresponding Author(s)
Other Contributor(s)
Abstract
Background: The kynurenine (KYN) pathway produces key metabolites for immunoregulation and neuromodulation in humans, but its presence and activity in the oral microbiome are unclear. This study investigates the functionality of the key kynureninase (KynU), which catalyses kynurenine to anthranilic acid (AA), in oral bacteria. Methods: Bioinformatic analysis identified putative kynU genes in oral bacterial genomes, and structural similarity of the predicted proteins was evaluated using Template Modeling (TM)-score and Root Mean Square Deviation (RMSD) analyses. Selected kynU sequences were cloned into the pBAD-His A expression vector. Enzymatic activity was accessed by quantifying AA concentrations using liquid chromatography-mass spectrometry (LC-MS). Results: Among 71 species, seven oral bacteria were identified to possess the kynU. Structural analyses indicated KynU from four species may fold into functional enzymes. Three recombinant KynU from Burkholderiacepacia, Ralstoniapickettii, and Stenotrophomonasmaltophilia produced detectable levels of AA (21.27 ± 12.0 µM, 19.59 ± 8.6 µM, and 46.43 ± 36.8 µM, respectively), confirming functional KYN-to-AA conversion. Conclusions: This study demonstrates KynU activity in oral bacteria, revealing an unrecognised aspect of microbial metabolism with potential implications for host-microbe interactions. Further investigation is required to elucidate the biological significance of bacterial KYN metabolites and their role in oral diseases.