Evaluation of the differences between biofilm and planktonic Brucella abortus via metabolomics and proteomics

The Flagellar Transcriptional Regulator FtcR Controls Brucella melitensis 16M Biofilm Formation via a betI-Mediated Pathway in Response to Hyperosmotic Stress

“…Next, we assessed the contribution of ftcR to biofilm formation under stress. To examine whether the biofilms formed by Δ ftcR could resist a range of hyperosmotic environmental stresses, we improved the B. abortus biofilm development method established by Tang et al [ 14 ]. First, we grew biofilms under various stress conditions for 20 d. After normalizing the biomass to the untreated control of each strain, we identified three strains with similar relative reductions in biomass after treatment with the osmotic solute.…”

“…We investigated the role of FtcR in the response of B. melitensis 16M biofilms to various conditions of environmental stress. Inconsistent with B. melitensis 16M in a planktonic state, the ftcR mutant showed a significant biofilm growth defect compared with that of the WT and complemented strains only under hyperosmotic stress; B. melitensis 16M did not show the same susceptibility to other stressors as the planktonic bacteria of the Δ ftcR strain, possibly highlighting the difference in the protective effects of the biofilm structure on bacteria and the bacteria in the planktonic state [ 11 , 14 , 15 ]. This biofilm phenotype was not a response to high concentrations of NaCl alone, because it was also observed when the biofilms were treated with other types of osmotic solutes.…”

“…Biofilms were cultured in 24-well plates as described by Tang et al [ 14 ] and Almirón et al [ 11 ], with some modifications. Briefly, Brucella Broth was inoculated with a single colony and cultured at 37 °C and 5% CO 2 with shaking at 150,000× g until growth reached the logarithmic phase, before being transferred (2 mL per well) into a 24-well cell culture plate with sterilized cover slips (8 × 8 mm, adhesion carrier).…”

“…Biofilms are formed by a complex process that initiates when microorganisms attach to a surface via an extracellular matrix and other adhesins that allow them to develop into large communities [ 13 ]. Compared to planktonic bacteria, biofilms have unique transcriptional and expressive programs [ 14 , 15 ]. Bacteria form a niche within these biofilms, exhibiting increased virulence and resistance to various hostile microenvironments [ 16 , 17 ].…”

Cadaverine Is a Switch in the Lysine Degradation Pathway in Pseudomonas aeruginosa Biofilm Identified by Untargeted Metabolomics

“…Metabolomics has been used to gain insight into the molecular mechanism of biofilm formation in other bacterial pathogens ( Yeom et al., 2013 ; Stipetic et al., 2016 ; Favre et al., 2018 ; Lu et al., 2019 ; Rieusset et al., 2020 ; Tang et al., 2021 ), but a comprehensive and quantitative analysis of metabolic changes involved in biofilm formation in P. aeruginosa is still missing ( Gjersing et al., 2007 ; Zhang and Powers, 2012 ; Borgos et al., 2015 ). Detailed elucidation of major shifts in metabolic pathways in planktonic versus biofilm phenotypes has the potential to identify mechanisms of metabolic regulation, new targets for prevention and mitigation, and specific metabolic signatures for diagnosis of biofilms.…”