AUTHOR=Eick Sigrun , Taudte Nadine , Ramsbeck Daniel , Magdoń Anna , Sculean Anton , Potempa Jan , Buchholz Mirko 

TITLE=Effect of a bacterial glutaminyl cyclase inhibitor on multi-species-biofilms

JOURNAL=Frontiers in Oral Health

VOLUME=Volume 6 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/oral-health/articles/10.3389/froh.2025.1716625

DOI=10.3389/froh.2025.1716625

ISSN=2673-4842

ABSTRACT=IntroductionModifying bacterial virulence could be an interesting alternative to antibiotics. The study aimed to examine the effects of an inhibitor targeting bacterial glutaminyl cyclase [which is selectively present in Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), and Prevotella intermedia (Pi)] on various multispecies biofilms.MethodsTwo multi-species biofilms—one containing four species (including Tf) and another with 12 species (including Tf, Pg, and Pi)—were cultured in the presence of 31.25–500 µM of a [4,5-c]pyridine-based inhibitor. After 24 h, bacterial counts, biofilm biomass, metabolic activity, and, when Pg was included, Arg-gingipain activity were measured. Additionally, the biofilms were exposed to monocytic cells; here, the release of interleukin (IL)-1β and IL-10 was analyzed. The data were analyzed using a one-way analysis of variance (ANOVA) with a post-hoc comparison performed using the Bonferroni correction.Results and DiscussionIn all biofilms, total bacterial counts and those of Pg and Tf remained unaffected by the inhibitor. In the 12-species biofilm, both biomass and total metabolic activity decreased at high inhibitor concentrations (500 µM to 75.2 ± 6.5% and 87.2 ± 5.8%, respectively; each p < 0.001). The arginine-specific amidolytic activities of Rgp declined dose-dependently, down to 60.4 ± 10.2% (p < 0.001) at 500 µM of the inhibitor. Consequently, Pg colonies lost pigmentation as inhibitor concentrations increased. The inhibitor also reduced IL-1β release from monocytic cells stimulated by the 12-species biofilm. The studied [4,5-c]pyridine-based inhibitor is able to modify virulence of a multispecies biofilm. It might have the potential to be a promising approach in periodontal prevention and therapy.