Microbial warfare in biofilms: microscopic and molecular insights into how B. subtilis targets the amyloid matrix of E. coli biofilms.

SERRA, D.O.

Rosario - Santa Fe

Congreso; L Reunión Anual de la Sociedad Argentina de Biofísica; 2022

Sociedad Argentina de Biofísica

Biofilms are multicellular communities that bacteria form by producing an extracellular matrix that protects and holds the cells together. Within biofilms, certain bacterial subpopulations recurrently tolerate and survive antibiotic treatments, which ultimately allow the resurgence of the biofilm community. As a consequence, biofilm formation allows many bacterial infections to persist, compromising the chance of cure. Recognizing the need for solutions to combat biofilm-based infections, we set out to explore microbial interactions in biofilms as a platform for the search of novel anti-biofilm compounds. While antagonistic interactions among microorganisms have been intensely exploited in the search for antibiotics, i.e., compounds that directly kill or inhibit bacterial growth, these microbial interactions have been overlooked regarding their potential as sources for compounds that modulate or interfere with biofilm formation. Here, I will present data -with emphasis on microscopy data– on how B. subtilis targets E. coli in biofilms through a secondary metabolite that combines two inhibitory functions in a concentration-dependent manner: at lower concentrations it inhibits the assembly of amyloid curli fibers rendering E. coli cells devoid of their extracellular matrix protection, whereas at higher concentrations (once cells are unshielded) it inhibits cell growth.