Use of a natural rock material as a precursor to inhibit corrosion of Ti alloy in an aggressive phosphoric acid medium.

The mechanism of interaction between magnesite mineral and phosphoric acid (0.001-0.5 M) in addition to the determination of the protective properties for Ti alloy (working electrode) in phosphoric acid both with and without an inhibitor have been investigated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements.

Fighting Celiac Disease: Improvement of pH Stability of Cathepsin L In Vitro by Computational Design.

Roughly 1% of the global population is susceptible to celiac disease (CD)-inheritable autoimmune inflammation of the small intestine caused by intolerance to gliadin proteins present in wheat, rye, and barley grains, and called gluten in wheat. Classical treatment is a life-long gluten-free diet, which is constraining and costly. An alternative approach is based upon the development and oral reception of effective peptidases that degrade in the stomach immunogenic proline- and glutamine-rich gliadin peptides, which are the cause of the severe reaction in the intestine.

Fatty Acid Profiles of Some Siberian Bryophytes and Prospects of Their Use in Chemotaxonomy.

The composition of fatty acids (FAs) in gametophyte samples of 20 Siberian bryophyte species from four orders of mosses and four orders of liverworts collected in relatively cold months (April and/or October) was examined. FA profiles were obtained using gas chromatography. Thirty-seven FAs were found, from 12:0 to 26:0; they included mono-, polyunsaturated (PUFAs) and rare FAs, such as 22:5n-3 and two acetylenic FAs, 6a,9,12-18:3 and 6a,9,12,15-18:4 (dicranin).

Complex of Proline-Specific Peptidases in the Genome and Gut Transcriptomes of Tenebrionidae Insects and Their Role in Gliadin Hydrolysis.

A detailed analysis of the complexes of proline-specific peptidases (PSPs) in the midgut transcriptomes of the larvae of agricultural pests and and in the genome of is presented. Analysis of the genome revealed 13 PSP sequences from the clans of serine and metal-dependent peptidases, of which 11 sequences were also found in the gut transcriptomes of both tenebrionid species' larvae. Studies of the localization of PSPs, evaluation of the expression level of their genes in gut transcriptomes, and prediction of the presence of signal peptides determining secretory pathways made it possible to propose a set of peptidases that can directly participate in the hydrolysis of food proteins in the larvae guts.

Recombinant Cathepsin L of and Its Potential in the Hydrolysis of Immunogenic Gliadin Peptides.

Wheat gliadins contain a large amount of glutamine- and proline-rich peptides which are not hydrolyzed by human digestive peptidases and can cause autoimmune celiac disease and other forms of gluten intolerance in predisposed people. Peptidases that efficiently cleave such immunogenic peptides can be used in enzyme therapy. The stored product insect pest efficiently hydrolyzes gliadins.

Density Functional Theory Approach to the Vibrational Properties and Magnetic Specific Heat of the Covalent Chain Antiferromagnet KFeS.

Ternary potassium-iron sulfide, KFeS, belongs to the family of highly anisotropic quasi-one-dimensional antiferromagnets with unusual "anti-Curie-Weiss" susceptibility, quasi-linearly growing with a rising temperature up to 700 K, an almost vanishing magnetic contribution to the specific heat, drastically reduced magnetic moment, etc. While some of the measurements can be satisfactorily described, the deficiency of the entropy changes upon the magnetic transition and the spin state of the iron ion remains a challenge for the further understanding of magnetism. In this work, high-quality single-crystalline samples of KFeS were grown by the Bridgman method, and their stoichiometry, crystal structure, and absence of alien magnetic phases were checked, utilizing wave-length dispersive X-ray electron-probe microanalysis, powder X-ray diffraction, and Fe Mössbauer spectroscopy, respectively.

Primary digestive cathepsins L of Tribolium castaneum larvae: Proteomic identification, properties, comparison with human lysosomal cathepsin L.

We previously described the most highly expressed enzymes from the gut of the red flour beetle, Tribolium castaneum, as cathepsins L. In the present study, two C1 family-specific cysteine cathepsin L enzymes from the larval midgut were isolated and identified using MALDI-TOF MS analysis. The isolated T.

Effective Degradation of Gluten and Its Fragments by Gluten-Specific Peptidases: A Review on Application for the Treatment of Patients with Gluten Sensitivity.

To date, there is no effective treatment for celiac disease (CD, gluten enteropathy), an autoimmune disease caused by gluten-containing food. Celiac patients are supported by a strict gluten-free diet (GFD). However, in some cases GFD does not negate gluten-induced symptoms.

Proline-Specific Fungal Peptidases: Genomic Analysis and Identification of Secreted DPP4 in Alkaliphilic and Alkalitolerant Fungi.

Proline-specific peptidases (PSP) play a crucial role in the processing of fungal toxins, pheromones, and intracellular signaling. They are of particular interest to biotechnology, as they are able to hydrolyze proline-rich oligopeptides that give a bitter taste to food and can also cause an autoimmune celiac disease. We performed in silico analysis of PSP homologs in the genomes of 42 species of higher fungi which showed the presence of PSP homologs characteristic of various kingdoms of living organisms and belonging to different families of peptidases, including homologs of dipeptidyl peptidase 4 (DPP4) and prolyl aminopeptidase 1 found in almost all the studied fungal species.

The dataset of predicted trypsin serine peptidases and their inactive homologs in transcriptomes.

is an important coleopteran model insect and agricultural pest from the Tenebrionidae family. We used RNA-Seq transcriptome data from to annotate trypsin-like sequences from the chymotrypsin S1 family of serine peptidases, including sequences of active serine peptidases (SerP) and their inactive homologs (SerPH) in transcriptomes. A total of 63 S1 family tryspin-like serine peptidase sequences were assembled.

New Glutamine-Containing Substrates for the Assay of Cysteine Peptidases From the C1 Papain Family.

New substrates with glutamine in the P1-position are introduced for the assay of peptidases from the C1 papain family, with a general formula of Glp-Phe-Gln-X, where Glp is pyroglutamyl and X is pNA (-nitroanilide) or AMC (4-amino-7-methylcoumaride). The substrates have a simple structure, and C1 cysteine peptidases of various origins cleave them with high efficiency. The main advantage of the substrates is their selectivity for cysteine peptidases of the C1 family.

Adsorption mechanisms of fatty acids on fluorite unraveled by infrared spectroscopy and first-principles calculations.

Hypothesis: The adsorption mechanisms of fatty acids on minerals are largely debated from years, and their understanding is now required to improve flotation processing in the critical context of raw materials. Three wavenumbers have been observed in the literature for the asymmetric stretching vibration of COO after the adsorption of fatty acids on mineral surfaces. They have been interpreted as different adsorbed forms, such as a precipitate formation, an adsorption of sole or bridged carboxylates, an anion exchange, or adsorbed modes, such as monodentate or bidentate configurations.

Human proline specific peptidases: A comprehensive analysis.

Background: Proline specific peptidases (PSPs) are a unique group of enzymes that specifically cleave bonds formed by a proline residue. The study of PSPs is important due to their role in the maturation and degradation of peptide hormones and neuropeptides. In addition, changes in the activity of PSPs can result in pathological conditions, including various types of cancer.

The Challenge of Tungsten Skarn Processing by Froth Flotation: A Review.

Recently, tungsten has drawn worldwide attention considering its high supply risk and economic importance in the modern society. Skarns represent one of the most important types of tungsten deposits in terms of reserves. They contain fine-grained scheelite (CaWO) associated with complex gangue minerals, i.

Synergistic adsorptions of NaCO and NaSiO on calcium minerals revealed by spectroscopic and molecular dynamics studies.

The synergistic effects between sodium silicate (NaSiO) and sodium carbonate (NaCO) adsorbed on mineral surfaces are not yet understood, making it impossible to finely tune their respective amounts in various industrial processes. In order to unravel this phenomenon, diffuse reflectance infrared Fourier transform and X-ray photoelectron spectroscopies were combined with molecular dynamics to investigate the adsorption of NaSiO onto bare and carbonated fluorite (CaF), an archetypal calcium mineral. Both experimental and theoretical results proved that NaCO adsorbs onto CaF with a high affinity and forms a layer of NaCO on the surface.

Green Process for Industrial Waste Transformation into Super-Oxidizing Materials Named Alkali Metal Ferrates (VI).

The investigation presented here features the design of a cleaner and greener chemical process for the conversion of industrial wastes into super-oxidizing materials. The waste of interest is the iron sulfate heptahydrate (FeSO·7HO) mainly generated through the sulfate route used for titanium dioxide industrial production. The products of this transformation process are alkali ferrates (AFeO, A = Na, K) containing iron in its hexavalent state and considered as powerful oxidants characterized by properties useful for cleaning waters, wastewaters, and industrial effluents.

Direct detection of cysteine peptidases for MALDI-TOF MS analysis using fluorogenic substrates.

A method is described for the direct detection of unstable cysteine peptidase activity in polyacrylamide gels after native electrophoresis using new selective fluorogenic peptide substrates, pyroglutamyl-phenylalanyl-alanyl-4-amino-7-methylcoumaride (Glp-Phe-Ala-AMC) and pyroglutamyl-phenylalanyl-alanyl-4-amino-7-trifluoromethyl-coumaride (Glp-Phe-Ala-AFC). The detection limit of the model enzyme papain was 17 pmol (0.29 μg) for Glp-Phe-Ala-AMC and 43 pmol (0.

Molecular Insight into Fatty Acid Adsorption on Bare and Hydrated (111) Fluorite Surface.

The adsorption of fatty acids with various chain structures on the (111) fluorite surface is investigated using density functional theory, including a correction for dispersive interactions. In the case of the acidic form, we observe that the molecular form is preferred over the dissociated one and the molecule adsorbs on a surface calcium atom with an energy of -78.2 kJ mol.

Surface Properties of Fluorite in Presence of Water: An Atomistic Investigation.

Density functional theory simulations, including a correction for dispersive interactions, were performed to investigate the adsorption of water on the main cleavage plane of the fluorite, namely, the (111) surface. In the case of a single molecule of water, we observe that the molecular form is preferred over the dissociated one, and absorbs on the surface with an energy of -55 kJ mol, including a significant contribution from the dispersion forces. Also, we show that the substitution of a fluorine atom by a hydroxyl group on the surface of fluorite is not energetically favorable.

Prolidase is a critical enzyme for complete gliadin digestion in Tenebrio molitor larvae.

Prolidase is a proline-specific metallopeptidase that cleaves imidodipeptides with C-terminal Pro residue. Prolidase was purified and characterized from the Tenebrio molitor larval midgut. The enzyme was localized in the soluble fraction of posterior midgut tissues, corresponding to a predicted cytoplasmic localization of prolidase according to the structure of the mRNA transcript.

Dipeptidyl peptidase 4 - An important digestive peptidase in Tenebrio molitor larvae.

Dipeptidyl peptidase 4 (DPP 4) is a proline specific serine peptidase that plays an important role in different regulatory processes in mammals. In this report, we isolated and characterized a unique secreted digestive DPP 4 from the anterior midgut of a stored product pest, Tenebrio molitor larvae (TmDPP 4), with a biological function different than that of the well-studied mammalian DPP 4. The sequence of the purified enzyme was confirmed by mass-spectrometry, and was identical to the translated RNA sequence found in a gut EST database.

GSTM1 copy number variation in the context of single nucleotide polymorphisms in the human GSTM cluster.

Background: GSTM1 gene deletion is one of the most known copy number polymorphisms in human genome. It is most likely caused by homologous recombination between the repeats flanking the gene. However, taking into account that the deletion has no crucial effects on human well-being, and the ability of other GSTMs to compensate for the lack of GSTM1, a role for additional factors affecting GSTM1 deletion can be proposed.

[Mechanisms of realization of protective effect of miliacin during experimental Salmonella infection: effect of endotoxinemia and cytokine production].

Aim: Evaluate the effect of miliacin on the intensity of endotoxinemia and features of cytokine production in experimental salmonella infection.

Materials And Methods: The studies were carried out in 128 male mice (CBAxC57Bl6)F1 divided into 4 groups: I--intact; II--infected; III--infected after administration of miliacin solvent: tween-21; IV--infected after administration of miliacin. Determination of the endotoxin in blood plasma was carried out by using chromogenic LAL-test.

[Analysis of a GSTM1 gene deletion in the context of the GSTM genomic cluster diversity in three Russian populations].

A total of 16 to 60% of individuals in human populations are homozygous with respect to a deletion of the Glutathione-S-transferase M1 gene. In this study, we evaluated the relationship between the GSTM1 gene deletion and genetic diversity of the GSTM cluster, which includes this gene, in three Russian populations. The study was based on the comparison of the haplotype distribution in two groups of individuals subdivided accordingly to the presence of the deletion.

[Soluble form of trigger receptor expressed on myeloid cells-1 as a marker of burn wound mixed infection].

Aim: Detection ofearly non-bacteriological markers ofburn wound mixed microbial infection.

Materials And Methods: The level of soluble form of trigger receptor expressed on myeloid cells-1 (sTREM-1) and cytokines in blood sera of 60 burn patients on days 3 - 6 and 10 - 17 after the burn was studied by solid phase enzyme immunoassay.

Results: At the early periods of burn disease the level ofsTREM- 1 in sera may be a non-bacteriological marker of burn wound mixed infection: at days 3 - 6 after the injury - higher than 298.