A whole-cell hypersensitive biosensor for beta-lactams based on the AmpR-AmpC regulatory circuit from the Antarctic Pseudomonas sp. IB20.

Detecting antibiotic residues is vital to minimize their impact. Yet, existing methods are complex and costly. Biosensors offer an alternative.

Surveillance of SARS-CoV-2, rotavirus, norovirus genogroup II, and human adenovirus in wastewater as an epidemiological tool to anticipate outbreaks of COVID-19 and acute gastroenteritis in a city without a wastewater treatment plant in the Peruvian Highlands.

The coronavirus disease 2019 (COVID-19) pandemic has demonstrated that Wastewater Based Epidemiology is a fast and economical alternative for monitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the community level in high-income countries. In the present study, wastewater from a city in the Peruvian Highlands, which lacks a wastewater treatment plant, was monitored for one year to assess the relationship between the concentration of SARS-CoV-2 and the reported cases of COVID-19 in the community. Additionally, we compared the relationship between rotavirus (RV), norovirus genogroup II (NoV GGII), and human adenovirus (HAdV) with the number of reported cases of acute gastroenteritis.

Commonalities between the Atacama Desert and Antarctica rhizosphere microbial communities.

Plant-microbiota interactions have significant effects on plant growth, health, and productivity. Rhizosphere microorganisms are involved in processes that promote physiological responses to biotic and abiotic stresses in plants. In recent years, the interest in microorganisms to improve plant productivity has increased, mainly aiming to find promising strains to overcome the impact of climate change on crops.

Metagenomic and Functional Characterization of Two Chilean Kefir Beverages Reveals a Dairy Beverage Containing Active Enzymes, Short-Chain Fatty Acids, Microbial β-Amyloids, and Bio-Film Inhibitors.

Kefir beverage is a probiotic food associated with health benefits, containing probiotic microorganisms and biomolecules produced during fermentation. The microbial composition of these beverages varies among countries, geographical regions, and the substrates, therefore, the characterization of kefir beverages is of great relevance in understanding their potential health-promoting and biotechnological applications. Therefore, this study presents the metagenomic and functional characterization of two Chilean kefir beverages, K02 and K03, through shotgun and amplicon-based metagenomic, microbiological, chemical, and biochemical studies.

Draft Genome Sequence of sp. Strain AL4B, a Marine Bacterium Isolated from Quintero Bay, Chile.

Quintero Bay, located along the central coast of Chile, has suffered different oil spills during the past 10 years, impacting its marine ecosystems. Here, we report the genome sequence of sp. strain AL4B, a marine bacterium isolated from Quintero Bay, Chile.

Probiotics and Prebiotics as a Strategy for Non-Alcoholic Fatty Liver Disease, a Narrative Review.

Non-alcoholic fatty liver disease (NAFLD) is a chronic non-communicable disease, with a prevalence of 25% worldwide. This pathology is a multifactorial illness, and is associated with different risks factors, including hypertension, hyperglycemia, dyslipidemia, and obesity. Beside these predisposing features, NAFLD has been related to changes in the microbiota, which favor the disease progression.

Gut Susceptibility to Viral Invasion: Contributing Roles of Diet, Microbiota and Enteric Nervous System to Mucosal Barrier Preservation.

The gastrointestinal lumen is a rich source of eukaryotic and prokaryotic viruses which, together with bacteria, fungi and other microorganisms comprise the gut microbiota. Pathogenic viruses inhabiting this niche have the potential to induce local as well as systemic complications; among them, the viral ability to disrupt the mucosal barrier is one mechanism associated with the promotion of diarrhea and tissue invasion. This review gathers recent evidence showing the contributing effects of diet, gut microbiota and the enteric nervous system to either support or impair the mucosal barrier in the context of viral attack.

A forecast model for prevention of foodborne outbreaks of non-typhoidal salmonellosis.

Background: This work presents a forecast model for non-typhoidal salmonellosis outbreaks.

Method: This forecast model is based on fitted values of multivariate regression time series that consider diagnosis and estimation of different parameters, through a very flexible statistical treatment called generalized auto-regressive and moving average models (GSARIMA).

Results: The forecast model was validated by analyzing the cases of serovar Enteritidis in Sydney Australia (2014-2016), the environmental conditions and the consumption of high-risk food as predictive variables.

Draft Genome Sequences of Lactobacillus plantarum Strain K03D08 and Acetobacter syzygii Strain K03D05, Isolated from a Kefir Beverage Collected in Chile.

Kefir is an ancestral food produced using microbial consortia whose composition varies depending on the geographical origin and the substrate used for fermentation. This dairy beverage is considered a probiotic food, and its consumption has been associated with several health benefits. This report describes the isolation of bacterial strains from Chilean kefir.

gen. nov., sp. nov., an acidophilic and obligately heterotrophic, member of the Actinobacteria that catalyses dissimilatory oxido-reduction of iron isolated from metal-rich acidic water in Chile.

A novel acidophilic member of the phylum was isolated from an acidic, metal-contaminated stream draining from an abandoned underground coal mine (Trongol mine), situated close to Curanilahue, Biobío Region, Chile. The isolate (USS-CCA1) was demonstrated to be a heterotroph that catalysed under aerobic conditions the oxidation of ferrous iron and the reduction of ferric iron under anaerobic conditions, but not the oxidation of sulfur nor hydrogen. USS-CCA1 is a Gram-positive, motile, short rod-shaped, mesophilic bacterium with a temperature growth optimum at 30 °C (range 20-39 °C).

Seawater salt-trapped Pseudomonas aeruginosa survives for years and gets primed for salinity tolerance.

Background: In nature, microorganisms have to adapt to long-term stressful conditions often with growth limitations. However, little is known about the evolution of the adaptability of new bacteria to such environments. Pseudomonas aeruginosa, an opportunistic pathogen, after natural evaporation of seawater, was shown to be trapped in laboratory-grown halite crystals and to remain viable after entrapment for years.

16S rRNA Amplicon Sequencing of Seawater Microbiota from Quintero Bay, Chile, Affected by Oil Spills, Shows the Presence of an Oil-Degrading Marine Bacterial Guild Structured by the Bacterial Genera , and .

The Quintero Bay, located along the central coast of Chile, has suffered different oil spills during the past 5 years, impacting marine ecosystems. This report describes the microbial community structure of seawater samples obtained from the Quintero Bay through 16S rRNA amplicon sequencing.

Parallel Evolution of High-Level Aminoglycoside Resistance in Under Low and High Mutation Supply Rates.

Antibiotic resistance is a major concern in public health worldwide, thus there is much interest in characterizing the mutational pathways through which susceptible bacteria evolve resistance. Here we use experimental evolution to explore the mutational pathways toward aminoglycoside resistance, using gentamicin as a model, under low and high mutation supply rates. Our results show that both normo and hypermutable strains of are able to develop resistance to drug dosages > 1,000-fold higher than the minimal inhibitory concentration for their ancestors.

The hydrocarbon-degrading marine bacterium Cobetia sp. strain MM1IDA2H-1 produces a biosurfactant that interferes with quorum sensing of fish pathogens by signal hijacking.

Biosurfactants are produced by hydrocarbon-degrading marine bacteria in response to the presence of water-insoluble hydrocarbons. This is believed to facilitate the uptake of hydrocarbons by bacteria. However, these diffusible amphiphilic surface-active molecules are involved in several other biological functions such as microbial competition and intra- or inter-species communication.

Biodesulfurization of gas oil using inorganic supports biomodified with metabolically active cells immobilized by adsorption.

The immobilization of Pseudomonas stutzeri using adsorption on different inorganic supports was studied in relation to the number of adsorbed cells, metabolic activity and biodesulfurization (BDS). The electrophoretic migration (EM) measurements and Tetrazolioum (TTC) method were used to evaluate adsorption and metabolic activity. Results indicate that maximal immobilization was obtained with an initial load of 14 x 10(8) cells mL(-1) for Al and Sep, whereas Ti requires 20 x 10(8) cells mL(-1).