Nature Reviews Microbiology, Journal Year: 2023, Volume and Issue: 22(2), P. 62 - 62
Published: Dec. 8, 2023
Language: Английский
Environmental Science & Technology, Journal Year: 2025, Volume and Issue: unknown
Published: Feb. 17, 2025
It has been widely accepted that iron plays an important role in stimulating the activity of anammox bacteria, which contain many clusters for electron transport cells. However, whether bacteria could directly use and how to uptake Fe(III) have long-time ignored. Here, we found micrometer-scale magnetite with size 10–20 μm significantly promoted bacterial by core uptake. Anammox cannot utilize as they are unable secrete siderophore extracellular transfer intracellular. In anaerobic consortia at presence magnetite, synthesis belonging Alphaproteobacteria, Candidate phylum, Chloroflexi secreted abundant siderophores, combined ionized from form siderophore-Fe(III) complexes. These complexes were then used via a specific outer membrane receptor transported transporter protein periplasm, further releasing Fe(III). Cytochrome c was formed complex reduction, assimilation Fe–S heme B increase capability. This study reveals siderophore-mediated cooperation implies driving nitrogen conversion artificial or natural system.
Language: Английский
Citations
1
bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown
Published: Jan. 4, 2025
Abstract Many bacteria use flagella to swim individually through bulk liquid, or swarm collectively over a semi-solid surface. In E. coli , c-di-GMP inhibits swimming via the effector protein YcgR. We show in this study that contrary its effect on swimming, certain threshold level of is required for swarming. Gene expression profiles first indicated several synthases – dgcJ, dgcM, dgcO - were upregulated during Of these, we found DgcO play critical role. reported affect PGA (poly-β-1,6-N-acetylglucosamine) synthesis . also promotes production colanic acid one three major exopolysaccharides and has hitherto-unknown surfactant properties are expected aid Importance It well-established bacteria, flagella-driven motility at various points pathway. Concomitantly, elevated levels induce variety enmesh biofilm, thereby interfering with function. This reports surprising finding exopolysaccharide enable surface navigation diguanylate cyclase employed purpose. For navigation, there appears be sweet spot where just right produce polysaccharides can serve as surfactants wetting agents rather than promote formation biofilms.
Language: Английский
Citations
0
Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(8)
Published: Feb. 19, 2025
Cell populations must adjust their phenotypic composition to adapt changing environments. One adaptation strategy is maintain distinct subsets within the population and modulate relative abundances via gene regulation. Another involves genetic mutations, which can be augmented by stress-response pathways. Here, we studied how a migrating bacterial regulates its distribution traverse diverse We generated isogenic Escherichia coli with varying distributions of swimming behaviors observed phenotype during migration in liquid porous found that became enriched high-performing phenotypes each environment, allowing without requiring mutations or This dynamic rapid, reversing few doubling times when ceases. By measuring chemoreceptor abundance toward different attractants, demonstrated acts on multiple chemotaxis-related traits simultaneously. These measurements are consistent general mechanism results from balance between cell growth generating diversity collective eliminating underperforming phenotypes. Thus, enables continuous, multidimensional flexibly rapidly environmental conditions.
Language: Английский
Citations
0
mBio, Journal Year: 2025, Volume and Issue: unknown
Published: May 6, 2025
ABSTRACT Many bacteria use flagella to swim individually through bulk liquid or swarm collectively over a semi-solid surface. In Escherichia coli , c-di-GMP inhibits swimming via the effector protein YcgR. We show in this study that, contrary its effect on swimming, certain threshold level of is required for swarming. Gene expression profiles first indicated that several synthases —dgcJ dgcM and dgcO —were upregulated during Of these, we found DgcO play critical role promoting production colanic acid—one three major exopolysaccharides E. . has been reported increase poly-β-1,6-N-acetylglucosamine (PGA) synthesis as well. acid hitherto-unknown surfactant properties are expected aid IMPORTANCE It well established bacteria, flagella-driven motility at various points pathway. Concomitantly, elevated levels induce variety enmesh biofilm, thereby also interfering with function. This reports surprising finding exopolysaccharide enable surface navigation diguanylate cyclase employed purpose. For navigation, there appears be sweet spot where just right produce polysaccharides can serve surfactants wetting agents rather than promote formation biofilms.
Language: Английский
Citations
0
bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown
Published: May 15, 2025
The emergence of transiently tolerant bacterial subpopulations challenges our understanding stress tolerance mechanisms. While much is known about antibiotic tolerance, it remains unclear whether similar mechanisms contribute to survival under ultraviolet (UV) stress. Here, we employed a modified Luria-Delbrück fluctuation test investigate the presence pre-existing UV-tolerant in Escherichia coli . Our results showed no significant evidence pre-stress UV tolerance. Instead, data suggest that primarily driven by inducible DNA repair responses activated after exposure. Furthermore, sequential low-dose exposures yielded higher-than-expected survival, suggesting transient can be induced following initial exposure, likely through active processes. These findings indicate E. survives via an induced, rather than pre-existing, mechanism
Language: Английский
Citations
0
bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown
Published: Jan. 3, 2024
Abstract Cell populations must adjust their phenotypic composition to adapt changing environments. One adaptation strategy is maintain distinct subsets within the population and modulate relative abundances via gene regulation. Another involves genetic mutations, which can be augmented by stress-response pathways. Here, we studied how a migrating bacterial regulates its distribution traverse diverse We generated isogenic Escherichia coli with varying distributions of swimming behaviors observed phenotype during migration in liquid porous found that became enriched high-performing phenotypes each environment, allowing without requiring mutations or This dynamic rapid, reversing few doubling times when ceases. By measuring chemoreceptor abundance towards different attractants, demonstrated acts on multiple chemotaxis-related traits simultaneously. These measurements are consistent general mechanism results from balance between cell growth generating diversity collective eliminating under-performing phenotypes. Thus, enables continuous, multi-dimensional flexibly rapidly environmental conditions. Significance statement Conventional mechanisms, like regulation stochastic switching, act swiftly but limited traits, while mutation-driven adaptations unfold slowly. quantifying migration, discovered an reversibly adjusts balancing generation through loss unable keep up, this process tunes environments they traverse, mutations. Given prevalence microbes, cancers, embryonic development, non-genetic may universal for navigate environments, offering insights into broader applications across various fields.
Language: Английский
Citations
2
Frontiers in Microbiomes, Journal Year: 2024, Volume and Issue: 3
Published: April 25, 2024
Language: Английский
Citations
2
Journal of Basic Microbiology, Journal Year: 2024, Volume and Issue: unknown
Published: Oct. 27, 2024
Poly(methyl methacrylate) (PMMA) resins are widely used in medical and dental applications. Their susceptibility to bacterial biofilm formation poses significant challenges related material degradation infection risk. This study investigated the effects of Pseudomonas aeruginosa (P. aeruginosa) Staphylococcus aureus (S. aureus) biofilms on PMMA resin surface properties over a 45-day period at 35°C. The examined various parameters including adhesion, morphology, roughness, hydrophobicity, solid fraction, zeta potential. specimens were inoculated with bacteria incubated for 45 days. Biofilm adhesion was visually assessed, while characterization conducted using scanning electron microscopy (SEM), atomic force (AFM), roughness analysis, contact angle measurements, fraction determination, potential analysis. P. S. isolates selected based their biofilm-positive characteristics, which further confirmed Congo red assays through crystal violet staining spectrophotometric results demonstrated robust surfaces. SEM AFM imaging revealed textured surfaces elevated structures depressions within matrix. Biofilm-exposed exhibited significantly increased (Ra = 164.5 nm, Rq 169.5 nm) hydrophobicity (mean 85.5°-90.5°) compared control samples 38-50 55°). Solid measurements indicated denser matrix exposed (0.908) controls (0.65). Additionally, values more negative biofilm-exposed -84.2 mV) than (-45.0 mV). These findings underscore substantial alterations induced by biofilms, emphasizing critical need strategies prevent mitigate associated risks healthcare settings. Future research should focus developing anti-biofilm coatings or treatments preserve integrity functionality materials.
Language: Английский
Citations
1
bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown
Published: Jan. 16, 2024
ABSTRACT Small RNAs (sRNAs) controlling gene expression by imperfect base-pairing with mRNA(s) are widespread in bacteria and regulate multiple genes, including genes involved iron homeostasis, through a wide variety of mechanisms. We previously showed that OmrA OmrB sRNAs repress the synthesis Escherichia coli FepA receptor for iron-enterobactin complexes. now report five additional sRNAs, namely RprA, RybB, ArrS, RseX SdsR, respond to different environmental cues, also fepA, independently one another. While RprA follows canonical mechanism pairing translation initiation region, repression ArrS or requires secondary structure far upstream within long fepA 5’UTR. demonstrate dual action whose 5’ end pairs region while its 3’ behaves like RseX. Strikingly, mutation analysis shows key role loops these intrinsic terminators regulation. Regulation furthermore depends on both Hfq chaperone RNase E endonuclease. Overall, our data strongly suggest levels must be tightly controlled under conditions, highlight diversity mechanisms underly regulation bacteria.
Language: Английский
Citations
0
Microorganisms, Journal Year: 2024, Volume and Issue: 12(9), P. 1888 - 1888
Published: Sept. 13, 2024
Persister cells (PCs), a subpopulation occurring within normal cells, exhibit transient tolerance to antibiotics because of their dormant state. PCs are categorized into two types: type I PCs, which emerge during the stationary phase, and II logarithmic phase. Using conventional colony-forming method, we previously demonstrated that
Language: Английский
Citations
0