Strain-Level Typing of Streptococcus pyogenes Using Optical DNA Mapping
Journal article, 2025

Streptococcus pyogenes, also known as group A Streptococcus (GAS), is a Gram-positive bacterial pathogen responsible for approximately 500,000 deaths globally per year. Therefore, surveillance of invasive GAS infections is of critical importance in understanding societal transmission. In this study, we propose an optical DNA mapping (ODM)-based assay for strain-level typing of S. pyogenes. Fluorescently labeled DNA molecules of lengths >150 kbp are stretched in nanochannels and imaged to reveal genomic information. A core genome alignment-based typing scheme is then utilized for identification at the strain level. Although our technique lacks the nucleotide-level resolution of whole-genome sequencing, it excels at detecting patterns across long stretches of DNA that remain inaccessible to short-read sequencing methods. Using clinical isolates, we demonstrate that the ODM assay can identify S. pyogenes at both the species level and at even higher taxonomic resolutions with high accuracy. Our typing scheme also shows a high correlation with standard emm subtyping for the analyzed samples. We conclude that ODM has the potential to deliver timely and cost-efficient strain-level bacterial identification.

diagnostics

nanofluidics

Streptococcus pyogenes

opticalDNA mapping

genomics

bacterial typing

Author

Radhika Nambannor Kunnath

Chalmers, Life Sciences, Chemical Biology

Center for Antibiotic Resistance Research in Gothenburg (CARe)

Zahra Abbaspour

Chalmers, Life Sciences, Chemical Biology

Anna Johnning

Chalmers, Mathematical Sciences, Applied Mathematics and Statistics

Fraunhofer-Chalmers Centre

University of Gothenburg

Center for Antibiotic Resistance Research in Gothenburg (CARe)

Karolin Frykholm

Chalmers, Life Sciences, Chemical Biology

Center for Antibiotic Resistance Research in Gothenburg (CARe)

Marie Wrande

Uppsala University

Albertas Dvirnas

Chalmers, Life Sciences, Chemical Biology

Lund University

Sriram Kesarimangalam

Center for Antibiotic Resistance Research in Gothenburg (CARe)

Chalmers, Life Sciences, Chemical Biology

Christian G. Giske

Karolinska University Hospital

Karolinska Institutet

Tobias Ambjornsson

Lund University

Linus Sandegren

Uppsala University

Erik Kristiansson

University of Gothenburg

Fredrik Westerlund

Center for Antibiotic Resistance Research in Gothenburg (CARe)

Chalmers, Life Sciences, Chemical Biology

ACS Infectious Diseases

2373-8227 (eISSN)

Vol. In Press

IDAR-Neo - Identification and characterization of fecal carriage of antimicrobial resistant bacteria in neonates in low-resource settings

Swedish Research Council (VR) (2022-03490), 2023-01-01 -- 2025-12-31.

Subject Categories (SSIF 2025)

Infectious Medicine

Microbiology in the Medical Area

Microbiology

Infrastructure

Myfab (incl. Nanofabrication Laboratory)

DOI

10.1021/acsinfecdis.5c00430

PubMed

41091517

More information

Latest update

10/24/2025