The Great Gobi A Strictly Protected Area: Characterization of Soil Bacterial Communities from Four Oases.

Understanding how microbial communities survive in extreme environmental pressure is critical for interpreting ecological patterns and microbial diversity. Great Gobi A Strictly Protected Area represents an intriguing model for studying the bacterial community since it is a protected and intact wild area of the Mongolian desert. In this work, the composition of a bacterial community of the soil from four oases was characterized by extracting total DNA and sequencing through the Illumina NovaSeq platform.

Employing Genome Mining to Unveil a Potential Contribution of Endophytic Bacteria to Antimicrobial Compounds in the L. Essential Oil.

Essential oils (EOs) from medicinal plants have long been used in traditional medicine for their widely known antimicrobial properties and represent a promising reservoir of bioactive compounds against multidrug-resistant pathogens. Endophytes may contribute to the yield and composition of EOs, representing a useful tool for biotechnological applications. In this work, we investigated the genomic basis of this potential contribution.

Mimicking the last step of gene elongation: hints from the bacterial hisF gene.

Gene elongation consists in an in-tandem duplication of a gene and divergence and fusion of the two copies, resulting in a gene constituted by two divergent paralogous modules. Many present-day proteins show internal repeats of amino acid sequences, generated by gene elongation events; however, gene elongation is still a poorly studied evolutionary molecular mechanism. The most documented case is that of the histidine biosynthetic genes hisA and hisF, which derive from the gene elongation of an ancestral gene half the size of the extant ones.

The Operon as a Conundrum of Gene Dynamics and Biochemical Constraints: What We Have Learned from Histidine Biosynthesis.

Operons represent one of the leading strategies of gene organization in prokaryotes, having a crucial influence on the regulation of gene expression and on bacterial chromosome organization. However, there is no consensus yet on why, how, and when operons are formed and conserved, and many different theories have been proposed. Histidine biosynthesis is a highly studied metabolic pathway, and many of the models suggested to explain operons origin and evolution can be applied to the histidine pathway, making this route an attractive model for the study of operon evolution.

Application of Cloning-Free Genome Engineering to .

The propagation of foreign DNA in is central to molecular biology. Recent advances have dramatically expanded the ability to engineer (bacterial) cells; however, most of these techniques remain time-consuming. The aim of the present work was to explore the possibility to use the cloning-free genome editing (CFGE) approach, proposed by Döhlemann and coworkers (2016), for genetics, and to deepen the knowledge about the homologous recombination mechanism.

Effect of Wastewater on the Composition of Bacterial Microbiota of Used in Constructed Wetlands for Phytodepuration.

Phytodepuration occurs in the plant-mediated remediation processes exploited to remove pollutants from wastewater, and is one of the most used plants. This goal is achieved using constructed wetlands (CW), which are engineered systems designed to mimic the natural processes of pollutants removal. The aim of this work was to characterize the bacterial communities associated to , soils, and permeates of the CW of Calice (Prato, Italy), to evaluate the possible effect of wastewaters on the CW bacterial communities, through a next-generation sequencing-based approach.

Endophytic Bacteria Associated with Origanum heracleoticum L. (Lamiaceae) Seeds.

Seed-associated microbiota are believed to play a crucial role in seed germination, seedling establishment, and plant growth and fitness stimulation, due to the vertical transmission of a core microbiota from seeds to the next generations. It might be hypothesized that medicinal and aromatic plants could use the seeds as vectors to vertically transfer beneficial endophytes, providing plants with metabolic pathways that could influence phytochemicals production. Here, we investigated the localization, the structure and the composition of the bacterial endophytic population that resides in L.

Unravelling the DNA sequences carried by Streptomyces coelicolor membrane vesicles.

Membrane vesicles (MVs) are spherical particles with nanoscale dimensions and characterized by the presence of diverse cargos, such as nucleic acids, proteins, lipids, and cellular metabolites. Many examples of (micro)organisms producing MVs are reported in literature. Among them, bacterial MVs are of particular interest because they are now considered as the fourth mechanism of horizontal gene transfer.

Endophytic Bacteria and Essential Oil from ssp. Share Some VOCs with an Antibacterial Activity.

Medicinal aromatic plants' essential oils (EOs) are mixtures of volatile compounds showing antimicrobial activity, which could be exploited to face the emerging problem of multi-drug resistance. Their chemical composition can depend on the interactions between the plant and its endophytic microbiota, which is known to synthesize volatile organic compounds (VOCs). However, it is still not clear whether those volatile metabolites can contribute to the composition of the aroma profile of plants' EOs.

Microbial Genetics and Evolution.

Although proto-evolutionary ideas date back to the time of the ancient Greeks, the idea that organisms evolve was not considered a basic element of scientific knowledge until Charles Darwin published his "On the Origin of Species" in 1859 [...

Genomic Analysis of Endophytic -Related Strains Isolated from the Medicinal Plant L. Revealed the Presence of Metabolic Pathways Involved in the Biosynthesis of Bioactive Compounds.

Multidrug-resistant pathogens represent a serious threat to human health. The inefficacy of traditional antibiotic drugs could be surmounted through the exploitation of natural bioactive compounds of which medicinal plants are a great reservoir. The finding that bacteria living inside plant tissues, (i.

Effect of Non-Lethal Selection on Spontaneous Revertants of Frameshift Mutations: The Escherichia coli hisF Case.

Microorganisms possess the potential to adapt to fluctuations in environmental parameters, and their evolution is driven by the continuous generation of mutations. The reversion of auxotrophic mutations has been widely studied; however, little is known about the reversion of frameshift mutations resulting in amino acid auxotrophy and on the structure and functioning of the protein encoded by the revertant mutated gene. The aims of this work were to analyze the appearance of reverse mutations over time and under different selective pressures and to investigate revertant enzymes' three-dimensional structures and their correlation with a different growth ability.

The Histidine Biosynthetic Genes in the Superphylum Bacteroidota-Rhodothermota-Balneolota-Chlorobiota: Insights into the Evolution of Gene Structure and Organization.

One of the most studied metabolic routes is the biosynthesis of histidine, especially in enterobacteria where a single compact operon composed of eight adjacent genes encodes the complete set of biosynthetic enzymes. It is still not clear how genes were organized in the genome of the last universal common ancestor community. The aim of this work was to analyze the structure, organization, phylogenetic distribution, and degree of horizontal gene transfer (HGT) of genes in the Bacteroidota-Rhodothermota-Balneolota-Chlorobiota superphylum, a group of phylogenetically close bacteria with different surviving strategies.

Antibacterial activity of bacteria isolated from against multidrug-resistant human pathogens.

Rising number of multidrug-resistant human pathogens demands novel antibiotics: to this aim, unexplored natural sources are investigated to find new compounds. In this context, bacteria associated to medicinal plants, including , might represent an important source of antimicrobial compounds. In the present work, 21 bacterial endophytes isolated from roots were tested, by cross-streaking, for their inhibitory activity against 36 multidrug-resistant pathogens isolated from food, clinical patients and hospitals.

Exploring the Gut Microbiome Alteration of the European Hare () after Short-Term Diet Modifications.

This study aimed to characterise the gut microbiome composition of European hares () and its potential changes after a short-term diet modification. The high sensitivity of European hare to habitat changes makes this species a good model to analyse possible alterations in gut microbiome after the introduction of additional nourishment into the diet. In total, 20 pairs were chosen for the experiments; 10 pairs formed the control group and were fed with standard fodder.

Temporal Evolution of Bacterial Endophytes Associated to the Roots of Exploited in Phytodepuration of Wastewater.

Improvement of industrial productions through more environment-friendly processes is a hot topic. In particular, land and marine environment pollution is a main concern, considering that recalcitrant compounds can be spread and persist for a long time. In this context, an efficient and cost-effective treatment of wastewater derived from industrial applications is crucial.

Exploring the role of the histidine biosynthetic hisF gene in cellular metabolism and in the evolution of (ancestral) genes: from LUCA to the extant (micro)organisms.

Histidine biosynthesis is an ancestral pathway that was assembled before the appearance of the Last Universal Common Ancestor; afterwards, it remained unaltered in all the extant histidine-synthesizing (micro)organisms. It is a metabolic cross-road interconnecting histidine biosynthesis to nitrogen metabolism and the de novo synthesis of purines. This interconnection is due to the reaction catalyzed by the products of hisH and hisF genes.

In vivo evaluation of the interaction between the Escherichia coli IGP synthase subunits using the Bacterial Two-Hybrid system.

Histidine biosynthesis is one of the most characterized metabolic routes for its antiquity and its central role in cellular metabolism; indeed, it represents a cross-road between nitrogen metabolism and de novo synthesis of purines. This interconnection is due to the activity of imidazole glycerol phosphate synthase, a heterodimeric enzyme constituted by the products of two his genes, hisH and hisF, encoding a glutamine amidotransferase and a cyclase, respectively. Despite their interaction was suggested by several in vitro experiments, their in vivo complex formation has not been demonstrated.

The Cultivable Bacterial Microbiota Associated to the Medicinal Plant L.: From Antibiotic Resistance to Growth-Inhibitory Properties.

The insurgence of antibiotic resistance and emergence of multidrug-resistant (MDR) pathogens prioritize research to discover new antimicrobials. In this context, medicinal plants produce bioactive compounds of pharmacological interest: some extracts have antimicrobial properties that can contrast different pathogens. For such a purpose, L.

The Role of Gene Elongation in the Evolution of Histidine Biosynthetic Genes.

Gene elongation is a molecular mechanism consisting of an in-tandem duplication of a gene and divergence and fusion of the two copies, resulting in a gene constituted by two divergent paralogous modules. The aim of this work was to evaluate the importance of gene elongation in the evolution of histidine biosynthetic genes and to propose a possible evolutionary model for some of them. Concerning the genes and , which code for two homologous (β/α)-barrels, it has been proposed that the two extant genes could be the result of a cascade of gene elongation/domain shuffling events starting from an ancestor gene coding for just one (β/α) module.