Integrated genome and metabolome mining unveiled structure and biosynthesis of novel lipopeptides from a deep-sea Rhodococcus.

Microbial biosurfactants have garnered significant interest from industry due to their lower toxicity, biodegradability, activity at lower concentrations and higher resistance compared to synthetic surfactants. The deep-sea Rhodococcus sp. I2R has been identified as a producer of glycolipid biosurfactants, specifically succinoyl trehalolipids, which exhibit antiviral activity.

Bioremediation for the recovery of oil polluted marine environment, opportunities and challenges approaching the Blue Growth.

The Blue Growth strategy promises a sustainable use of marine resources for the benefit of the society. However, oil pollution in the marine environment is still a serious issue for human, animal, and environmental health; in addition, it deprives citizens of the potential economic and recreational advantages in the affected areas. Bioremediation, that is the use of bio-resources for the degradation of pollutants, is one of the focal themes on which the Blue Growth aims to.

New Imidazolium Alkaloids with Broad Spectrum of Action from the Marine Bacterium .

The continuous outbreak of drug-resistant bacterial and viral infections imposes the need to search for new drug candidates. Natural products from marine bacteria still inspire the design of pharmaceuticals. Indeed, marine bacteria have unique metabolic flexibility to inhabit each ecological niche, thus expanding their biosynthetic ability to assemble unprecedented molecules.

Evaluation of Antimicrobial Properties and Potential Applications of M15 Rhamnolipids towards Multiresistant .

is a Gram-positive opportunistic human pathogen responsible for severe infections and thousands of deaths annually, mostly due to its multidrug-resistant (MDR) variants. The cell membrane has emerged as a promising new therapeutic target, and lipophilic molecules, such as biosurfactants, are currently being utilized. Herein, we evaluated the antimicrobial activity of a rhamnolipids mixture produced by the Antarctic marine bacterium M15.

Exploring Oceans for Curative Compounds: Potential New Antimicrobial and Anti-Virulence Molecules against .

Although several antibiotics are already widely used against a large number of pathogens, the discovery of new antimicrobial compounds with new mechanisms of action is critical today in order to overcome the spreading of antimicrobial resistance among pathogen bacteria. In this regard, marine organisms represent a potential source of a wide diversity of unique secondary metabolites produced as an adaptation strategy to survive in competitive and hostile environments. Among the multidrug-resistant Gram-negative bacteria, is undoubtedly one of the most important species due to its high intrinsic resistance to different classes of antibiotics on the market and its ability to cause serious therapeutic problems.

Enhanced production of biobased, biodegradable, Poly(3-hydroxybutyrate) using an unexplored marine bacterium Pseudohalocynthiibacter aestuariivivens, isolated from highly polluted coastal environment.

The production and disposal of plastics from limited fossil reserves, has prompted research for greener and sustainable alternatives. Polyhydroxyalkanoates (PHAs) are biocompatible, biodegradable, and thermoprocessable polyester produced by microbes. PHAs found several applications but their use is limited due to high production cost and low yields.

Novel Insights on Pyoverdine: From Biosynthesis to Biotechnological Application.

Pyoverdines (PVDs) are a class of siderophores produced mostly by members of the genus . Their primary function is to accumulate, mobilize, and transport iron necessary for cell metabolism. Moreover, PVDs also play a crucial role in microbes' survival by mediating biofilm formation and virulence.

Antiviral Activity of the Rhamnolipids Mixture from the Antarctic Bacterium M15 against Herpes Simplex Viruses and Coronaviruses.

Emerging and re-emerging viruses represent a serious threat to human health at a global level. In particular, enveloped viruses are one of the main causes of viral outbreaks, as recently demonstrated by SARS-CoV-2. An effective strategy to counteract these viruses could be to target the envelope by using surface-active compounds.

Right atrium enlargement is related to increased heart damage and mortality in well-controlled hypertension.

Background And Aim: Left heart remodeling is a well-known pathophysiological effect of arterial hypertension. Right Heart status is not considered in its evaluation. No data are available on right atrium (RA) and its impact on the outcome in hypertension.

Isolation and Characterization of Strain sp. KRL4, a Producer of Bioactive Secondary Metabolites from a Tibetan Glacier.

Extremophilic microorganisms represent a unique source of novel natural products. Among them, cold adapted bacteria and particularly alpine microorganisms are still underexplored. Here, we describe the isolation and characterization of a novel Gram-positive, aerobic rod-shaped alpine bacterium (KRL4), isolated from sediments from the Karuola glacier in Tibet, China.

Characterization of a New Mixture of Mono-Rhamnolipids Produced by Isolated from Edmonson Point (Antarctica).

Rhamnolipids (RLs) are surface-active molecules mainly produced by Antarctica is one of the less explored places on Earth and bioprospecting for novel RL producer strains represents a promising strategy for the discovery of novel structures. In the present study, 34 cultivable bacteria isolated from Edmonson Point Lake, Ross Sea, Antarctica were subjected to preliminary screening for the biosurfactant activity. The positive strains were identified by 16S rRNA gene sequencing and the produced RLs were characterized by liquid chromatography coupled to high resolution mass spectrometry (LC-HRESIMS) and liquid chromatography coupled with tandem spectrometry (LC-MS/MS), resulting in a new mixture of 17 different RL congeners, with six previously undescribed RLs.

Harvesting of Prebiotic Fructooligosaccharides by Nonbeneficial Human Gut Bacteria.

Prebiotic oligosaccharides, such as fructooligosaccharides, are increasingly being used to modulate the composition and activity of the gut microbiota. However, carbohydrate utilization analyses and metagenomic studies recently revealed the ability of deleterious and uncultured human gut bacterial species to metabolize these functional foods. Moreover, because of the difficulties of functionally profiling transmembrane proteins, only a few prebiotic transporters have been biochemically characterized to date, while carbohydrate binding and transport are the first and thus crucial steps in their metabolization.

Drain fluid's pH predicts anastomotic leak in colorectal surgery: results of a prospective analysis of 173 patients.

Background: The early risk assessment of anastomotic leak (AL) after colorectal surgery is crucial. Several markers have been proposed, including peritoneal fluid's pH. Aim of the present study is to evaluate the role of drain fluid pH as predictor of AL.

The art of adapting to extreme environments: The model system Pseudoalteromonas.

Extremophilic microbes have adapted to thrive in ecological niches characterized by harsh chemical/physical conditions such as, for example, very low/high temperature. Living organisms inhabiting these environments have developed peculiar mechanisms to cope with extreme conditions, in such a way that they mark the chemical-physical boundaries of life on Earth. Studying such mechanisms is stimulating from a basic research viewpoint and because of biotechnological applications.

Antibiotics from Deep-Sea Microorganisms: Current Discoveries and Perspectives.

The increasing emergence of new forms of multidrug resistance among human pathogenic bacteria, coupled with the consequent increase of infectious diseases, urgently requires the discovery and development of novel antimicrobial drugs with new modes of action. Most of the antibiotics currently available on the market were obtained from terrestrial organisms or derived semisynthetically from fermentation products. The isolation of microorganisms from previously unexplored habitats may lead to the discovery of lead structures with antibiotic activity.

Identification of a Sorbicillinoid-Producing Aspergillus Strain with Antimicrobial Activity Against Staphylococcus aureus: a New Polyextremophilic Marine Fungus from Barents Sea.

The exploration of poorly studied areas of Earth can highly increase the possibility to discover novel bioactive compounds. In this study, the cultivable fraction of fungi and bacteria from Barents Sea sediments has been studied to mine new bioactive molecules with antibacterial activity against a panel of human pathogens. We isolated diverse strains of psychrophilic and halophilic bacteria and fungi from a collection of nine samples from sea sediment.

Pseudoalteromonas haloplanktis TAC125 produces 4-hydroxybenzoic acid that induces pyroptosis in human A459 lung adenocarcinoma cells.

In order to exploit the rich reservoir of marine cold-adapted bacteria as a source of bioactive metabolites, ethyl acetate crude extracts of thirteen polar marine bacteria were tested for their antiproliferative activity on A549 lung epithelial cancer cells. The crude extract from Pseudoalteromonas haloplanktis TAC125 was the most active in inhibiting cell proliferation. Extensive bioassay-guided purification and mass spectrometric characterization allowed the identification of 4-hydroxybenzoic acid (4-HBA) as the molecule responsible for this bioactivity.

High-Throughput Flow Cytometry Screening of Multidrug Efflux Systems.

The resistance nodulation cell division (RND) family of proteins are inner membrane transporters that associate with periplasmic adaptor proteins and outer membrane porins to affect substrate transport from the cytosol and periplasm in Gram-negative bacteria. Various structurally diverse compounds are substrates of RND transporters. Along with their notable role in antibiotic resistance, these transporters are essential for niche colonization, quorum sensing, and virulence as well as for the removal of fatty acids and bile salts.

Evaluation of Complex Bacteria Pathogenicity Using .

This protocol describes two biological assays to evaluate pathogenicity of complex (Bcc) strains against the nematode Specifically, these two assays allow one to identify if the under-investigated Bcc strains are able to kill the nematodes by intestinal colonization (slow killing assay, SKA) or by toxins production (fast killing assay, FKA). The principal differences between the two assays rely on the different killing kinetics for worms.

Pseudoalteromonas haloplanktis produces methylamine, a volatile compound active against Burkholderia cepacia complex strains.

The Antarctic marine bacterium Pseudoalteromonas haloplanktis TAC125 has been reported to produce several Volatile Organic Compounds (VOCs), which are able to inhibit the growth of Burkholderia cepacia complex (Bcc) strains, opportunistic pathogens responsible for the infection of immune-compromised patients. However, no specific antibacterial VOCs have been identified to date. The purpose of the present study was to identify specific VOCs that contribute to Bcc inhibition by the Antarctic strain.

Cryo-protective effect of an ice-binding protein derived from Antarctic bacteria.

Cold environments are populated by organisms able to contravene deleterious effects of low temperature by diverse adaptive strategies, including the production of ice binding proteins (IBPs) that inhibit the growth of ice crystals inside and outside cells. We describe the properties of such a protein (EfcIBP) identified in the metagenome of an Antarctic biological consortium composed of the ciliate Euplotes focardii and psychrophilic non-cultured bacteria. Recombinant EfcIBP can resist freezing without any conformational damage and is moderately heat stable, with a midpoint temperature of 66.

The antimicrobial potential of algicolous marine fungi for counteracting multidrug-resistant bacteria: phylogenetic diversity and chemical profiling.

Marine fungi represent an important but still largely unexplored source of novel and potentially bioactive secondary metabolites. The antimicrobial activity of nine sterile mycelia isolated from the green alga Flabellia petiolata collected from the Mediterranean Sea was tested on four antibiotic-resistant bacterial strains using extracellular and intracellular extracts obtained from each fungal strain. The isolated fungi were identified at the molecular level and assigned to one of the Dothideomycetes, Sordariomycetes or Eurotiomycetes classes.

Antimicrobial Activity of Monoramnholipids Produced by Bacterial Strains Isolated from the Ross Sea (Antarctica).

Microorganisms living in extreme environments represent a huge reservoir of novel antimicrobial compounds and possibly of novel chemical families. Antarctica is one of the most extraordinary places on Earth and exhibits many distinctive features. Antarctic microorganisms are well known producers of valuable secondary metabolites.

Investigating the Role of the Host Multidrug Resistance Associated Protein Transporter Family in Burkholderia cepacia Complex Pathogenicity Using a Caenorhabditis elegans Infection Model.

This study investigated the relationship between host efflux system of the non-vertebrate nematode Caenorhabditis elegans and Burkholderia cepacia complex (Bcc) strain virulence. This is the first comprehensive effort to profile host-transporters within the context of Bcc infection. With this aim, two different toxicity tests were performed: a slow killing assay that monitors mortality of the host by intestinal colonization and a fast killing assay that assesses production of toxins.

Identification and characterization of a novel salt-tolerant esterase from a Tibetan glacier metagenomic library.

A salt-tolerant esterase, designated H9Est, was identified from a metagenomic library of the Karuola glacier. H9Est gene comprised 1071 bp and encoded a polypeptide of 357 amino acids with a molecular mass of 40 kDa. Sequence analysis revealed that H9Est belonged to the family IV of bacterial lypolitic enzyme.