A5013232838- Selenium in Biological Systems
- Nanoparticles: synthesis and applications
- Arsenic contamination and mitigation
- Enzyme Production and Characterization
- Polar Research and Ecology
- CRISPR and Genetic Engineering
- Microbial Community Ecology and Physiology
- Trace Elements in Health
- Bacterial Genetics and Biotechnology
- Advanced Nanomaterials in Catalysis
- Enzyme Catalysis and Immobilization
- Biofuel production and bioconversion
- Heavy Metal Exposure and Toxicity
- Chromium effects and bioremediation
- Heat shock proteins research
- Enzyme Structure and Function
- GABA and Rice Research
- Gut microbiota and health
- Diet, Metabolism, and Disease
- Sugarcane Cultivation and Processing
- Organoselenium and organotellurium chemistry
- Cell Image Analysis Techniques
- Heme Oxygenase-1 and Carbon Monoxide
- Genomics and Phylogenetic Studies
- Redox biology and oxidative stress
Max Planck Unit for the Science of Pathogens
2021-2024
Charité - Universitätsmedizin Berlin
2023-2024
ETH Zurich
2024
Department of Medical Sciences
2024
Universidad de Santiago de Chile
2014-2023
Hospital Vozandes
2019
The high neuroactive potential of metabolites produced by gut microbes has gained traction over the last few years, with metagenomic-based studies suggesting an important role microbiota-derived γ-aminobutyric acid (GABA) in modulating mental health. Emerging evidence revealed presence glutamate decarboxylase (GAD)-encoding gene, a key enzyme to produce GABA, prominent human intestinal genus Bacteroides . Here, we investigated GABA production culture and metabolic assays combined comparative...
Tellurium, a metalloid belonging to group 16 of the periodic table, displays very interesting physical and chemical properties lately has attracted significant attention for its use in nanotechnology. In this context, microorganisms synthesizing nanostructures emerges as an eco-friendly exciting approach compared their synthesis. To generate Te-containing nanostructures, bacteria enzymatically reduce tellurite elemental tellurium. work, using classic biochemical approach, we looked novel...
Abstract The bactericidal activity of several antibiotics partially relies on the production reactive oxygen species (ROS), which is generally linked to enhanced respiration and requires Fenton reaction. Bacterial persister cells, an important cause recurring infections, are tolerant these because they in a dormant state. Here, we use Bacillus subtilis cells stationary phase, as model system show that pharmacological induction membrane depolarization enhances antibiotics’ also leads ROS...
Abstract The metalloid tellurite is highly toxic to microorganisms. Several mechanisms of action have been proposed, including thiol depletion and generation hydrogen peroxide superoxide, but none them can fully explain its toxicity. Here we use a combination directed evolution chemical biochemical approaches demonstrate that inhibits heme biosynthesis, leading the accumulation intermediates this pathway hydroxyl radical. Unexpectedly, development resistance accompanied by increased...
The tellurium oxyanion tellurite (TeO3 (2-)) is extremely harmful for most organisms. It has been suggested that a potential bacterial resistance mechanism would consist of an enzymatic, NAD(P)H-dependent, reduction to the less toxic form elemental (Te(0)). To date, number enzymes such as catalase, type II NADH dehydrogenase and terminal oxidases from electron transport chain, nitrate reductases, dihydrolipoamide (E3), among others, have shown display tellurite-reducing activity. This...
The Psychrobacter genus is a cosmopolitan and diverse group of aerobic, cold-adapted, Gram-negative bacteria exhibiting biotechnological potential for low-temperature applications including bioremediation. Here, we present the draft genome sequence bacterium from isolated sediment sample King George Island, Antarctica (3,490,622 bp; 18 scaffolds; G + C = 42.76%). Using phylogenetic analysis, biochemical properties scanning electron microscopy was identified as glacincola BNF20, making it...
Microbes are suitable candidates to recover and decontaminate different environments from soluble metal ions, either via reduction or precipitation generate insoluble, non-toxic derivatives. In general, microorganisms reduce toxic ions generating nanostructures (NS), which display great applicability in biotechnological processes. Since the molecular bases of bacterial still unknown, search for new -environmentally safe less expensive- methods synthesize NS have made biological systems...
Abstract Background There is an emerging field to put into practice new strategies for developing molecules with antimicrobial properties. In this line, several metals and metalloids are currently being used these purposes, although their cellular effect(s) or target(s) in a particular organism still unknown. Here we aimed investigate analyze Au 3+ toxicity through combination of biochemical molecular approaches. Results We found that triggers major oxidative unbalance Escherichia coli ,...
To describe a clinical case of Acinetobacter baumannii sequence type (ST) 32 harbouring New Delhi metallo-β-lactamase (NDM) in Ecuador. We used multilocus typing (MLST) to confirm the bacterial species and an A. isolate. synergy with imipenem–EDTA disc method carbapenem inactivation (CIM) determine carbapenemase production; presence gene was confirmed by PCR amplification amplicon sequencing. Molecular characterization revealed ST32 blaNDM-1 The isolated through amplified from purified...
Metal(loid) salts were used to treat infectious diseases in the past due their exceptional biocidal properties at low concentrations. However, mechanism of toxicity has yet be fully elucidated. The production reactive oxygen species (ROS) been linked soft metal(loid)s such as Ag(I), Au(III), As(III), Cd(II), Hg(II), and Te(IV). Nevertheless, few reports have described direct, or ROS-independent, effects some these soft-metal(loid)s on bacteria, including dismantling iron-sulfur clusters...
The goal of this work was to enhance tellurite toxicity against Gram positive bacteria, especially Staphyloccocus aureus. Using a combination assays (growth inhibition zones, growth curves, and minimal inhibitory concentrations), bacterium tested in the presence various SH- OH-containing compounds. Results showed that noxiousness strongly enhanced 2-mercaptoethanol or dithiothreitol. potentiating effect observed S. aureus ATCC 6538 (the model organism study) other bacteria such as Bacillus...
Tellurium is a rare metalloid that exerts high toxicity on cells, especially bacteria, partly due to reactive oxygen species (ROS) generation. Moreover, it has also been observed tellurite can target free cell thiols groups (RSH) (i.e. reduced glutathione (GSH)), enhancing the cellular redox imbalance. Additionally, in vitro experiments have suggested several enzymes reduce (IV) its elemental form (0); where RSH present their active sites may be responsible for process. Nevertheless,...
Initiation of bacterial DNA replication takes place at the origin (
<title>Abstract</title> The production of gamma-aminobutyric acid (GABA) by the gut microbiota has garnered attention due to its potential role in gut-brain axis. However, regulatory mechanisms governing microbiota-derived GABA under physiologically relevant conditions remain unclear. Here, using model GABA-producing microbe <italic>Bacteroides thetaiotaomicron</italic>, we identified intestinal environmental factors that modulate production. We demonstrate low pH and high osmolality promote...
Abstract We could demonstrate that the AAA+ unfoldase ClpC together with protein arginine kinase and adaptor McsB, its activator McsA phosphatase YwlE form a unique chaperone system. Here, McsA-activated McsB phosphorylates targets aggregated substrate proteins for extraction unfolding by ClpC. Sub-stoichiometric amounts of enhanced ClpC/McsB/McsA mediated disaggregation facilitated de-phosphorylation arginine-phosphorylated extruded ClpC, allowing subsequent refolding. Interestingly,...
Abstract Metal(loid) salts have been used to treat infectious diseases due their exceptional biocidal properties at low concentrations. However, the mechanism of toxicity has yet be fully elucidated. The production reactive oxygen species (ROS) linked soft metal(loid)s such as Ag(I), Au(III), As(III), Cd(II), Hg(II), and Te(IV). Nevertheless, few reports described direct, or ROS-independent, effects some these soft-metal(loid)s on bacteria, including dismantling iron-sulphur clusters...