New AI-based methods for studying antibiotic-resistant bacteria
Abstract
Antibiotic resistance is a growing challenge for human health, causing millions of deaths worldwide annually. Antibiotic resistance genes (ARGs), acquired through mutations in existing genes or horizontal gene transfer, are the primary cause of bacterial resistance. In clinical settings, the increased prevalence of multidrug-resistant bacteria has severely compromised the effectiveness of antibiotic treatments. The rapid development of artificial intelligence (AI) has facilitated the analysis and interpretation of complex data and provided new possibilities to face this problem. This is demonstrated in this thesis, where new AI methods for the surveillance and diagnostics of antibiotic-resistant bacteria are presented in the form of three scientific papers.
Paper I presents a comprehensive characterization of the resistome in various microbial communities, covering both well-studied established ARGs and latent ARGs not currently found in existing repositories. A widespread presence of latent ARGs was observed in all examined environments, signifying a potential reservoir for recruitment to pathogens. Moreover, some latent ARGs exhibited high mobile potential and were located in human pathogens. Hence, they could constitute emerging threats to human health. Paper II introduces a new AI-based method for identifying novel ARGs from metagenomic data. This method demonstrated high performance in identifying short fragments associated with 20 distinct ARG classes with an average accuracy of 96. The method, based on transformers, significantly surpassed established alignment-based techniques. Paper III presents a novel AI-based method to predict complete antibiotic susceptibility profiles using patient data and incomplete diagnostic information. The method incorporates conformal prediction and accurately predicts, while controlling the error rates, susceptibility profiles for the 16 included antibiotics even when diagnostic information was limited.
The results presented in this thesis conclude that recent AI methodologies have the potential to improve the diagnostics and surveillance of antibiotic-resistant bacteria.
Parts of work
Inda-Díaz, J.S., Lund, D., Parras-Moltó, M., Johnning, A., Bengtsson-Palme, J., and Kristiansson, E. (2023). Latent antibiotic resistance genes are abundant, diverse, and mobile in human, animal, and environmental microbiomes. Microbiome 11(44), https://doi.org/10.1186/s40168-023-01479-0 Inda-Díaz, J.S., Johnning, A., Hessel, M., Sjöberg, A., Lokrantz, A., Helldal, L., Jirstrand, M., Svensson, L., and Kristiansson, E. (2023). Confidence-based Prediction of Antibiotic Resistance at the Patient-level Using Transformers. bioRxiv 2023.05.09.539832, doi: https://doi.org/10.1101/2023.05.09.539832 Inda-Díaz, J.S., Örtenberg-Toftås, M., Salomonsson, E., Berglund, F., Johnning, A., and Kristiansson, E. (2023). Identification of short fragments of antibiotic-resistance genes using transformers. Manuscript
Degree
Doctor of Philosophy
University
University of Gothenburg. Faculty of Science.
Institution
Department of Mathematical Sciences ; Institutionen för matematiska vetenskaper
Disputation
Fredagen den 24 november 2023, kl. 9.00, Hörsal Euler, Chalmers Tekniska Högskola, Chalmers tvärgata 3, 412 58 Göteborg
Date of defence
2023-11-24
inda@chalmers.se
Date
2023-11-03Author
Inda Díaz, Juan Salvador
Keywords
Transformers, Antibiotic Resistance, Infectious Diseases, Metagenomics, Data-driven Diagnostics
Publication type
Doctoral thesis
ISBN
978-91-8069-503-9 (print) and/or 978-91-8069-504-6 (PDF)
Language
eng