Cell‐Wall‐Targeting Antibiotics Cause Lag‐Phase Bacteria to Form Surface‐Mediated Filaments Promoting the Formation of Biofilms and Aggregates

Abstract

Antibiotics are known to promote bacterial formation of enhanced biofilms, the mechanism of which is not well understood. Here, using biolayer interferometry, we have shown that bacterial cultures containing antibiotics that target cell walls cause biomass deposition on surfaces over time with a linear profile rather than the Langmuir‐like profiles exhibited by bacterial adherence in the absence of antibiotics. We observed about three times the initial rate and 12 times the final biomass deposition on surfaces for cultures containing carbenicillin than without. Unexpectedly, in the presence of antibiotics, the rate of biomass deposition inversely correlated with bacterial densities from different stages of a culture. Detailed studies revealed that carbenicillin caused faster growth of filaments that were seeded on surfaces from young bacteria (from lag phase) than those from high‐density fast‐growing bacteria, with rates of filament elongation of about 0.58 and 0.13 μm min−1, respectively. With surfaces that do not support bacterial adherence, few filaments were observed even in solution. These filaments aggregated in solution and formed increased amounts of biofilms on surfaces. These results reveal the lifestyle of antibiotic‐induced filamentous bacteria, as well as one way in which the antibiotics promote biofilm formation.

Aminophenol-Decorated Gold Nanoparticles for Curing Bacterial Infections

“…The prevalence of multidrug resistant bacteria (MDR) strains is a worldwide healthcare issue − and over 70% of bacterial infections are resistant to one or more of the antibiotics , that are generally used to eradicate infections. − Thus, it is urgent to develop novel antibiotics to overcome the disadvantage of the conventional antibiotics. Recent advances in antimicrobial nanomaterials have made nanotechnology a powerful solution to this dilemma. − Nanomaterials may become the mainstream in treating bacterial infections due to the high antibacterial efficacy and multiple antibacterial mechanisms. − Among nanomaterials, gold nanoparticles (Au NPs) have high surface-to-volume ratio, precise controlled surfaces, unique optical properties, and low toxicity, − making them promising candidates for developing nanoscale antibiotics.…”

Environmental Stress, Bacterial Cell Differentiation, and Antimicrobial Resistance

“…Similarly, polyploidy facilitates DNA mutational repair by homologous recombination, or CRISP-Cas mediated adaptive immunity (Bos et al 2015, Wang et al 2019. Also, filamentation favors bacterial adhesion to biological or inert surfaces (Möller et al, 2013); perhaps, adhesion is required for effective filamentation (Jin et al, 2020), including microbiotic particles where different organisms coalesce (Baquero et al, 2022), where nutrients also accumulate. On surfaces, filamentation facilitates biofilm formation (Anbumani et al, 2021;Yoon et al, 2011), and probably functions associated with quorum sensing (Chuang et al, 2019).…”