Draft Genome Sequences of Nine Bacillus Strains and Two Weizmannia Strains Isolated from Live Dietary Supplements and a Cultured Food Product

We present the genome sequences of nine Bacillus isolates and two Weizmannia isolates from 10 different dietary supplements and one cultured food product. Strains of these species have been associated with health benefits when ingested by humans, due to their ability to survive the stomach’s acidic environment and colonize the intestinal tract.

Escherichia coli YigI is a conserved γ-proteobacterial acyl-CoA thioesterase permitting metabolism of unusual fatty acid substrates

Thioesterases play a critical role in metabolism, membrane biosynthesis, and overall homeostasis for all domains of life. In this present study, we characterize a putative thioesterase from Escherichia coli MG1655 and define its role as a cytosolic enzyme. Building on structure-guided functional predictions, we show that YigI is a medium- to -long chain acyl-CoA thioesterase that is involved in the degradation of conjugated linoleic acid (CLA) in vivo, showing overlapping specificity with two previously defined E. coli thioesterases TesB and FadM. We then bioinformatically identify the regulatory relationships that induce YigI expression, which include: an acidic environment, high oxygen availability, and exposure to aminoglycosides. Our findings define a role for YigI and shed light on why the E. coli genome harbors numerous thioesterases with closely related functions.

Acidic Tumor Microenvironment Promotes Pancreatic Cancer through miR-451a/MEF2D Axis

Pancreatic cancer (PC), as a highly malignant and aggressive solid tumor, is common in the digestive system. The acidic microenvironment is one of the critical markers of cancer. Nonetheless, there are few studies on how the acidic microenvironment affects the development of PC. This study focused on investigating the specific molecular mechanisms of the acidic microenvironment in PC. In our study, qRT-PCR was conducted for examining microRNA (miR)-451a and myocyte enhancer factor 2D (MEF2D) expressions in PANC-1 cells. Then, detailed functional effects of an acidic environment on miR-451a and MEF2D in PANC-1 cells were detected by CCK-8, colony formation, flow cytometry, wound healing, transwell, mitochondrial functionality measurement, JC-1 staining, DCFH-DA staining, and sphere formation assays. The relationship between miR-451a and MEF2D was confirmed by luciferase reporter analysis. Under acidic conditions, the increase of proliferation, migration, and invasion of PANC-1 cells was observed. Moreover, the mitochondrial oxidative respiration-related gene miR-451a was reduced in acidic conditions. In addition, we found that, in PANC-1 cells under an acidic environment, miR-451a overexpression enhanced oxygen consumption, mitochondrial membrane potential (MMP) loss, and ROS generation and inhibited proliferation, migration, invasion, and stemness via sponging MEF2D. In a word, our results revealed that the acidic microenvironment regulated PC progression by affecting the miR-451a/MEF2D axis, indicating a novel avenue for the future treatment of PC.

The anti-nutritional effect of phytates - the extraphosphorus effect of phytase (review)

An analytical review was conducted on the availability of phosphorus from phytates, which increase the inclusion of phytase in the feed, while not only phytic acid is broken down, but also as a result of a decrease in concentration reduces its anti-nutritional effect.Phosphorus from plant feeds is not fully available to animals, as it is part of phytates, the cleavage of which in the gastrointestinal tract (gastrointestinal tract) of animals is limited. Phytates, getting into the acidic environment of the stomach, ionize and react with positively charged minerals, proteins, amino acids, creating compounds inaccessible for further digestion. The inclusion of phytase in compound feed is accompanied by an extra phosphoric effect, which is expressed in an increase in the availability of amino acids and energy. The decision on the feasibility of including phytase in feed is made on the basis of production tests of the proposed drugs.The studies carried out by the authors of invitro confirm the assumption that phytates enter into chemical interactions with peptides, as well as amino acids formed in the processes of protein digestion, turning them into compounds inaccessible to absorption. The proposed explanation does not affect the results of the balance experiment, but allows us to develop the study of the mechanism in terms of the interaction of digested amino acids with phytates. Based on this, another conclusion can be seen: the destruction of phytates should occur in the body before the digestion and dissolution of protein. In birds, this place is the goiter and stomachs, in pigs - the stomach. The hydrolysis of newly formed phytates (FC-amino acid) requires phytases that are active in the environment of the small intestine at pH 6 -7. As a result, the bound amino acids will be re-released and available for absorption. The development of new phytase preparations, taking into account the proposed explanation, will make it possible to create more effective feed preparations.

Mineral waters and sediments of the ferruginous spring Ulan-Bulak Urulyunguevsky (South-Eastern Transbaikalia, Russia)

The data on the chemical composition and content of balneological components (Fe, H2SiO3, CO2, S2-) for three water samples from the Ulan-Bulak acidic ferruginous spring are presented. For the first time, carbonic water was released in the composition of the spring waters, the origin of which is explained by the ingress of hydrocarbonate water into an acidic medium, followed by dissociation according to the HCO3 - + H+ → H2CO3 → H2O + CO2 scheme. An acidic environment is formed as a result of oxidation of sulfide mineralization, presumably gold-bearing. From secondary minerals at the spring, modern sulfate minerals (gypsum, jarosite), hydromica (illite) were found, ocher sediments are widely developed. Given the uncertain nature of the formation of the spring waters, it is considered worthy of special studies, including an inspection of the presence of sulfide mineralization.

Stable and Efficient Photoinduced Charge Transfer of MnFe2O4/Polyaniline Photoelectrode in Highly Acidic Solution

Tailoring conductive polymers with inorganic photocatalysts, which provide photoinduced electron-hole generation, have significantly enhanced composites leading to excellent photoelectrodes. In this work, MnFe2O4 nanoparticles prepared by a hydrothermal method were combined with polyaniline to prepare mixed (hybrid) slurries, which were cast onto flexible FTO to prepare photoelectrodes. The resulting photoelectrodes were characterized by XRD, FESEM, HRTEM and UV-VIS. The photoelectrochemical performance was investigated by linear sweep voltammetry and chronoamperometry. The photocurrent achieved by MnFe2O4/Polyaniline was 400 μA/cm2 at 0.8 V vs. Ag/AgCl in Na2SO4 (pH = 2) at 100 mW/cm2, while polyaniline alone achieved only 25 μA/cm2 under the same conditions. The best MnFe2O4/Polyaniline displayed an incident photon-to-current conversion efficiency (IPCE) and applied bias photon-to-current efficiency (ABPE) of 60% at 405 nm wavelength, and 0.17% at 0.8 V vs. Ag/AgCl, respectively. High and stable photoelectrochemical performance was achieved for more than 900 s in an acidic environment.