SKM 2023 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
BP: Fachverband Biologische Physik
BP 6: Bacterial Mechanics
BP 6.1: Vortrag
Montag, 27. März 2023, 15:00–15:15, BAR 0106
Antigenic variation modulates attractive forces between bacteria and affects antibiotic tolerance — •Isabelle Wielert1,3, Sebastian Kraus-Römer1,3, Paul Higgins2,3, and Berenike Maier1,3 — 1Institute for Biological Physics, University of Cologne, Germany — 2Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Germany — 3Center for Molecular Medicine Cologne
Type 4 pili (T4P) are multifunctional surface exposed polymers involved in adhesion, force generation, surface motility, aggregation and act as major antigens. During antigenic variation, the human pathogen Neisseria gonorrhoeae varies the primary structure of the pilin, the major subunit of the T4P fibre, to escape from immune surveillance. But it is unclear how pilin antigenic variation impacts other T4P functions. We addressed this question by replacing the pilin of a laboratory strain by pilins from various clinical isolates. By performing dual laser trap experiments, we found that the pilin variant strains clustered into two groups with different attractive forces. Variants with interaction forces exceeding 40 pN formed colonies while weakly interacting bacteria retained a planktonic lifestyle. All pilin variants supported surface motility, yet the planktonic variants moved faster. Previous studies indicated that bacterial aggregation results in higher tolerance against antibiotic treatment. To test whether pilin antigenic variation affects tolerance, we carried out bacterial survival assays and showed that indeed colony-forming variants are more tolerant. We conclude that pilin variation enhances bacterial fitness beyond immune escape.