Molecular docking of ursolic acid and Staphylococcus aureus ATPase for antibacterial therapy

Antibiotics have transformed the practice of medicine, making once lethal infections easily treatable and making other medical advances possible. The abuse of antibiotics has contributed to the growing problem of antibiotic resistance, which has become one of the most serious and growing threats to public health. Ursolic acid is one of the most promising substances of biological origin for antimicrobial therapy. A molecular docking with Staphylococcus aureus ATPase is presented

Italian “Vessalico” garlic ecotype: characterization of sulfur compounds and antiviral activity against Tomato brown rugose fruit virus (ToBRFV)

Many varieties or cultivars of garlic are available, due to the high environmen- tal adaptative ability of the species, and they can be selected and identified based on morphological, biochemical, and chemical data [1,2]. In this study Vessalico garlic, one of the best-known Italian garlic ecoytpes, was compared with Messidrôme and Messidor, whose cloves are used for sowing, and with the geographically adjacent Caraglio ecotype. UHPLC‐Q-trap analyses of the extracts of 52 garlic accessions belonging to these four ecotypes showed similar profiles for sulfur compounds, highlighting the presence of typical molecules of stored garlic. This result was consistent with the usual storage of commercial garlic bulbs at cellar temperature for six-eight months after harvest, to ensure year-round supply for customers. HC, PCA and SOM, ap- plied to the LC/MS data, allowed to separate the four ecotypes, identifying three sub-classes in the accessions of Vessalico ecotype, and confirming sim- ilarities between Vessalico and French accessions. All garlic extracts showed ability to deactivate Tomato brown rugose fruit vi- rus (ToBRFV) and Pepino mosaic virus (PepMV) infectivity, as a possible conse- quence of disassembly of the virus coat protein (CP). Molecular docking showed a strong interaction of the sulfur compounds characteristic of aged extracts with a high number of residues into ToBRFV CP binding site, interfer- ing with virulence progress. This result could be a good starting point for the possible use of garlic extracts as antiviral agent in organic agriculture, as re- covery of waste product or unsold at the season en

A new tool to investigate the structural characteristics of sesterterpenoids in marine and terrestrial organisms

The design of a relational database, based on highly controlled taxonomies and ontologies [1], that will form the core of a site open to interdisciplinary collaboration is presented [2,3]. In the logical scheme (▶ Fig. 1) the centrality of the organism concept in relation to the compound whose chemical classes, activities and extraction mechanisms are stored is highlighted. Bibliographic information covers the years from 1918 to 2022. The sesterterpenoids are classified based on their structural complexity, from linear pentaprenyl, to car- bocyclic and heterocyclic ring-containing scaffolds. Marine and terrestrial or- ganisms, including higher plants and insects are reported. Phylum Porifera is the richest source, yet the original producers are often believed to be their as- sociated microbes, even if scarcely proved. Certain spongivore molluscs bio- accumulate or biotransform sponge-derived sesterterpenoids for their own defense, while a few molluscs and cnidarians produce them de novo. In envi- ronmental and human pathogenic microorganisms, the production of sester- terpenoids changes in response to stressors and dictates fluctuation in com- plex microbial communities. Bioactivities as antimicrobial, ichthyo- and phy- to-toxic, nematocidal, anticancer, anti-inflammatory, and modulation of neu- rodegenerative processes are reported, as well as activity in the treatment of metabolic diseases such as type-II diabetes, hypercholesterolemia and obesity and as immunosuppressive molecules. For each compound information about the extraction procedure is provided, including pretreatment of the sample, solvent(s) of extraction and partitioning, and analytical technique. The data- base is built and tested with data provided by all co-authors. At present, over 350 living organisms (from 4 kingdoms) producing more than 1300 com- pounds have been catalogued

Small membranous proteins of the TorE/NapE family, crutches for cognate respiratory systems in Proteobacteria

Abstract In this report, we investigate small proteins involved in bacterial alternative respiratory systems that improve the enzymatic efficiency through better anchorage and multimerization of membrane components. Using the small protein TorE of the respiratory TMAO reductase system as a model, we discovered that TorE is part of a subfamily of small proteins that are present in proteobacteria in which they play a similar role for bacterial respiratory systems. We reveal by microscopy that, in Shewanella oneidensis MR1, alternative respiratory systems are evenly distributed in the membrane contrary to what has been described for Escherichia coli. Thus, the better efficiency of the respiratory systems observed in the presence of the small proteins is not due to a specific localization in the membrane, but rather to the formation of membranous complexes formed by TorE homologs with their c-type cytochrome partner protein. By an in vivo approach combining Clear Native electrophoresis and fluorescent translational fusions, we determined the 4:4 stoichiometry of the complexes. In addition, mild solubilization of the cytochrome indicates that the presence of the small protein reinforces its anchoring to the membrane. Therefore, assembly of the complex induced by this small protein improves the efficiency of the respiratory system

The nature of the electron acceptor (MnIV/NO3) triggers the differential expression of genes associated with stress and ammonium limitation responses in Shewanella algae C6G3

Shewanella algae C6G3 can dissimilatively reduce nitrate into ammonium and manganese oxide (MnIV) into MnII. It has the unusual ability to anaerobically produce nitrite from ammonium in the presence of MnIV. To gain insight into their metabolic capabilities, global mRNA expression patterns were investigated by RNA-seq and qRT-PCR in cells growing with lactate and ammonium as carbon and nitrogen sources, and with either MnIV or nitrate as electron acceptors. Genes exhibiting higher expression levels in the presence of MnIV belonged to functional categories of carbohydrate, coenzyme, lipid metabolisms and inorganic ion transport. The comparative transcriptomic pattern between MnIV and NO3 revealed that the strain presented an ammonium limitation status with MnIV, despite the presence of a non-limiting concentration of ammonium under both culture conditions. In addition, in the presence of MnIV, ntrB/nrtC regulators, ammonium channel, nitrogen regulatory protein P-II, glutamine synthetase and asparagine synthetase glutamine-dependent genes were over-represented. Under the nitrate condition, the expression of genes involved in the synthesis of several amino acids was increased. Finally, the expression level of genes associated with the general stress response was also amplified in both conditions and among them, katE, a putative catalase/peroxidase present on several Shewanella genomes, was highly expressed with a median value relatively higher in the MnIV condition

The synergistic effect of time of exposure, distance and no use of personal protective equipment in the determination of SARS-CoV-2 infection: Results of a contact tracing follow-up study in healthcareworkers

The aim of this study is to assess the effect of contact time, contact distance and the use of personal protective equipment on the determination of SARS-CoV-2 infection in healthcare workers (HCWs). This study consists of an analysis of data gathered for safety reasons at the Sapienza Teaching Hospital Policlinico Umberto I in Rome through the surveillance system that was put into place after the worsening of the COVID-19 pandemic. The studied subjects consist of HCWs who were put under health surveillance, i.e., all employees who were in contact with subjects who were confirmed to have tested positive for SARS-CoV-2. The HCWs under surveillance were monitored for a period encompassing ten days after the date of contact, during which they undertook nasopharyngeal swab tests analysed through RT-PCR (RealStar®SARS-CoV-2 Altona Diagnostic-Germany). Descriptive and univariate analyses have been undertaken, considering the following as risk factors: (a) no personal protective equipment use (PPE); (b) Distance < 1 m between the positive and contact persons; (c) contact time > 150. Finally, a Cox regression and an analysis of the level of synergism between factors, as specified by Rothman, were carried out. We analysed data from 1273 HCWs. Of these HCWs, 799 (62.8%) were females, with a sample average age of 47.8 years. Thirty-nine (3.1%) tested positive during surveillance. The overall incidence rate was 0.4 per 100 person-days. Time elapsed from the last exposure and a positive RT-PCR result ranged from 2 to 17 days (mean = 7, median = 6 days). In the univariate analysis, a distance <1 m and a contact time > 150 proved to be risk factors for the SARS-CoV-2 infection, with a hazard ratio (HR) of 2.62 (95% CI: 1.11-6.19) and 3.59 (95% IC: 1.57-8.21), respectively. The synergism analysis found the highest synergism between the “no PPE use” x “Contact time”. The synergy index S remains strongly positive also in the analysis of the factors “no PPE use” x “Distance” and “Time of contact” x “Distance”. This study confirms the absolute need to implement safety protocols during the pandemic and to use the correct PPE within health facilities in order to prevent SARS-CoV-2 infection. The analysis shows that among the factors considered (contact time and distance, no use of PPE), there is a strong synergistic effect