Neuromicrobiology, an emerging neurometabolic facet of the gut microbiome?

The concept of the gut microbiome is emerging as a metabolic interactome influenced by diet, xenobiotics, genetics, and other environmental factors that affect the host’s absorption of nutrients, metabolism, and immune system. Beyond nutrient digestion and production, the gut microbiome also functions as personalized polypharmacy, where bioactive metabolites that our microbes excrete or conjugate may reach systemic circulation and impact all organs, including the brain. Appreciable evidence shows that gut microbiota produce diverse neuroactive metabolites, particularly neurotransmitters (and their precursors), stimulating the local nervous system (i.e., enteric and vagus nerves) and affecting brain function and cognition. Several studies have demonstrated correlations between the gut microbiome and the central nervous system sparking an exciting new research field, neuromicrobiology. Microbiome-targeted interventions are seen as promising adjunctive treatments (pre-, pro-, post-, and synbiotics), but the mechanisms underlying host-microbiome interactions have yet to be established, thus preventing informed evidence-based therapeutic applications. In this paper, we review the current state of knowledge for each of the major classes of microbial neuroactive metabolites, emphasizing their biological effects on the microbiome, gut environment, and brain. Also, we discuss the biosynthesis, absorption, and transport of gut microbiota-derived neuroactive metabolites to the brain and their implication in mental disorders

BACTIBASE: a new web-accessible database for bacteriocin characterization

<p>Abstract</p> <p>Background</p> <p>Bacteriocins are very diverse group of antimicrobial peptides produced by a wide range of bacteria and known for their inhibitory activity against various human and animal pathogens. Although many bacteriocins are now well characterized, much information is still missing or is unavailable to potential users. The assembly of such information in one central resource such as a database would therefore be of great benefit to the exploitation of these bioactive molecules in the present context of increasing antibiotic resistance and natural bio-preservation need.</p> <p>Description</p> <p>In the present paper, we present the development of a new and original database BACTIBASE that contains calculated or predicted physicochemical properties of 123 bacteriocins produced by both Gram-positive and Gram-negative bacteria. The information in this database is very easy to extract and allows rapid prediction of relationships structure/function and target organisms of these peptides and therefore better exploitation of their biological activity in both the medical and food sectors.</p> <p>Conclusion</p> <p>The BACTIBASE database is freely available at <url>http://bactibase.pfba-lab.org</url>, web-based platform enabling easy retrieval, via various filters, of sets of bacteriocins that will enable detailed analysis of a number of microbiological and physicochemical data.</p

BACTIBASE second release: a database and tool platform for bacteriocin characterization

<p>Abstract</p> <p>Background</p> <p>BACTIBASE is an integrated open-access database designed for the characterization of bacterial antimicrobial peptides, commonly known as bacteriocins.</p> <p>Description</p> <p>For its second release, BACTIBASE has been expanded and equipped with additional functions aimed at both casual and power users. The number of entries has been increased by 44% and includes data collected from published literature as well as high-throughput datasets. The database provides a manually curated annotation of bacteriocin sequences. Improvements brought to BACTIBASE include incorporation of various tools for bacteriocin analysis, such as homology search, multiple sequence alignments, Hidden Markov Models, molecular modelling and retrieval through our taxonomy Browser.</p> <p>Conclusion</p> <p>The provided features should make BACTIBASE a useful tool in food preservation or food safety applications and could have implications for the development of new drugs for medical use. BACTIBASE is available at <url>http://bactibase.pfba-lab-tun.org</url>.</p

Bacteriocins as a new generation of antimicrobials : toxicity aspects and regulations

In recent decades, bacteriocins have received substantial attention as antimicrobial compounds. Although bacteriocins have been predominantly exploited as food preservatives, they are now receiving increased attention as potential clinical antimicrobials and as possible immune-modulating agents. Infections caused by antibiotic-resistant bacteria have been declared as a global threat to public health. Bacteriocins represent a potential solution to this worldwide threat due to their broad- or narrow-spectrum activity against antibiotic-resistant bacteria. Notably, despite their role in food safety as natural alternatives to chemical preservatives, nisin remains the only bacteriocin legally approved by regulatory agencies as a food preservative. Moreover, insufficient data on the safety and toxicity of bacteriocins represent a barrier against the more widespread use of bacteriocins by the food and medical industry. Here, we focus on the most recent trends relating to the application of bacteriocins, their toxicity and impacts

The expected number of olympic medals: a case study of team Portugal at Tokyo 2020

The 2020 Summer Olympic Games reached to an end in Tokyo, Japan. Even though all the hiccups, constraints, and challenges imposed by the COVID-19 pandemic, the Games were successfully held in August 2021. For the first time in history, Team Portugal won four medals (one gold, one silver, and two bronzes). In 2018 the Portuguese Olympic Committee signed a contract with the Portuguese Institute of Sport and Youth (i.e., Portuguese government) listing the deliverables of the mission Tokyo 2020 against a funding scheme of 18.5 million euros (Contrato n.º 33-A/2018; Contrato -Programa de Desenvolvimento Desportivo n.º CP/1/DDF/2018). The document sets, among other goals and deliverables, that no less than two medals would be won at Tokyo 2020 (section IV.1. of the contract). On the road to Tokyo, Portugal got more than two medallists at World Championships in several Olympic sports. Indeed, there were six to eight potential medallists at the 2020 Olympic Games (O Jogo, 2021). There is evidence that just one-third to one-fourth of the Olympic athletes are able to excel and outperform at the Olympic Games. In the sport of competitive swimming, just 29.82% of all male Olympians and 53.84% of the finalists at Rio 2016 improved their entry times (Barbosa, 2016a). On average, only 30% of the swimmers were able to improve their entry time at the 2012 and 2016 Olympic Games (Barbosa, 2016b). At Rio 2016, Team Portugal was expected to win two medals out of nine potential medallists, i.e., almost 25% of effectiveness (Garcia, 2016). Thus, one can wonder if the Portuguese Olympic Committee was sensible, assuming that two athletes would reach the podium spot out of six to eight potential medallists. Also, it begs the question if the four medals won were an outstanding achievement, deemed as a substantial improvement of the Portuguese sports system or, if alternatively, the Portuguese Olympic Committee underestimated the number of medals that the country could win.info:eu-repo/semantics/publishedVersio

Fate and Biological Activity of the Antimicrobial Lasso Peptide Microcin J25 Under Gastrointestinal Tract Conditions

The bacteriocin microcin J25 (MccJ25) inhibits the growth of Gram-negative pathogens including Salmonella and Shigella species, and Escherichia coli. This 21-amino acid peptide has remarkable stability to heat and extreme pH values and resistance to many proteases, thanks to a characteristic lasso structure. In this study, we used the dynamic simulator TIM-1 as gastro-intestinal tract model to evaluate the stability and antibacterial activity of MccJ25 during passage through the proximal portion of the human gastrointestinal tract. MccJ25 concentration was measured in the different simulator sections by HPLC, and inhibition of Salmonella enterica serotype Enteritidis was evaluated using qualitative and quantitative assays. LC-MS/MS analysis and subsequent molecular networking analysis on the Global Natural Product Social Molecular Networking platform (GNPS) and analysis of the peptide degradation in the presence of proteolytic enzymes mimicking the gastro-intestinal conditions permitted to delineate the fate of MccJ25 through identification of the main degradation products. MccJ25 was relatively stable under gastric conditions, but degraded rapidly in the compartment mimicking the duodenum, notably in the presence of pancreatin. Among pancreatin components, elastase I appeared primarily responsible for MccJ25 breakdown, while α-chymotrypsin was less efficient

Improved recovery of antioxidant compounds from refined pumpkin peel extract: a mixture design method approach

This study employed the mixture design method to determine optimal solvent combinations, aiming to obtain refined extracts from squash peels with enhanced antioxidant properties. We optimized extraction solvents, focusing on recovering the total phenolic compounds (TPC) and increased antioxidant properties using a second-order polynomial equation through the response surface methodology (RSM). Six solvents (MeOH, Hexane, DCM, EtOAc, BuOH, and water) were assessed for their effects on TPC and antioxidant activity in preliminary experiments. The refined extracts underwent a HPLC analysis for a phenolic composition determination and were further evaluated for their antibacterial activity and cytotoxicity. The results revealed a rich phenolic content in the refined extract from peels of Bejaoui landrace, primarily catechin (8.06 mg/g dry extract (DE)), followed by epicatechin and kaempferol (5 mg/g DE). Antibacterial tests against Enterococcus faecalis, Pseudomonas aeruginosa, Salmonella typhimurium, and Staphylococcus aureus showed significant antimicrobial activities, especially for Karkoubi and batati landraces, where the growth inhibitions were 99%, 96%, 97%, and 80% and 94%, 89%, 98%, and 96% for the respective bacteria. The peel extracts exhibited a negligible cytotoxicity on the RAW264.7 cell line, even at high concentrations. Our findings emphasize the potential antioxidant and antibacterial properties of peel extracts due to diverse phenolic compounds, suggesting the potential use of squash peels in the food and nutraceuticals industries as sources of natural antimicrobial agents.This study was supported by the Tunisian Ministry of Higher Education and Scientific Research and was funded under the scope of the Project PulpIng-H2020-PRIMA 2019—Section 2—Multi-topic 2019. To the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2020); to FCT for the contract of L. Barros (CEEC Institutional); to the General Secretariat for Research and Technology of the Ministry of Development and Investments under the PRIMA Program. PRIMA is an Art.185 initiative supported and co-funded under Horizon 2020, the European Union’s Program for Research and Plants 2022, 11, 800 16 of 18 Innovation (Prima2019-08).info:eu-repo/semantics/publishedVersio

DetoxiProt: an integrated database for detoxification proteins

<p>Abstract</p> <p>Background</p> <p>Detoxification proteins are a class of proteins for degradation and/or elimination of endogenous and exogenous toxins or medicines, as well as reactive oxygen species (ROS) produced by these materials. Most of these proteins are generated as a response to the stimulation of toxins or medicines. They are essential for the clearance of harmful substances and for maintenance of physiological balance in organisms. Thus, it is important to collect and integrate information on detoxification proteins.</p> <p>Results</p> <p>To store, retrieve and analyze the information related to their features and functions, we developed the DetoxiProt, a comprehensive database for annotation of these proteins. This database provides detailed introductions about different classes of the detoxification proteins. Extensive annotations of these proteins, including sequences, structures, features, inducers, inhibitors, substrates, chromosomal location, functional domains as well as physiological-biochemical properties were generated. Furthermore, pre-computed BLAST results, multiple sequence alignments and evolutionary trees for detoxification proteins are also provided for evolutionary study of conserved function and pathways. The current version of DetoxiProt contains 5956 protein entries distributed in 628 organisms. An easy to use web interface was designed, so that annotations about each detoxification protein can be retrieved by browsing with a specific method or by searching with different criteria.</p> <p>Conclusions</p> <p>DetoxiProt provides an effective and efficient way of accessing the detoxification protein sequences and other high-quality information. This database would be a valuable source for toxicologists, pharmacologists and medicinal chemists. DetoxiProt database is freely available at <url>http://lifecenter.sgst.cn/detoxiprot/</url>.</p