Protein-carbohydrate Complexes Research Articles

Development of industrial feed for channel catfish grown in the Central Federal District of the Russian Federation

In the result of the analysis of domestic experience over the last 10 years of foreign experience (for example, 9 countries: Vietnam, India, Spain, Canada, China, Norway, USA, Chile, Japan, which possess the most advanced technologies and equipment for highly efficient production of feed for fish) in the development of innovative technologies and equipment for production of high-performance fish feeds were identified that the methods both dry and wet pressing are outdated and do not meet modern requirements in the production of fish feeds since it does not allow a deep physical-chemical transformations in protein-carbohydrate complex and exercise enter fat components at 40 %. Modern fish technologies are based on the use of extrusion processing of multicomponent mixture to give different buoyancy and adjustable rate of immersion of the resulting feed. Extrusion technology will allow to introduce a large amount of fat into the product - up to 35-40 %, to achieve 100 % starch splitting level. Based on the study of the nutrition of the canal catfish grown in the Central Federal District of the Russian Federation, the nutritional value of each of the components of the feed mixture, providing the need for fish to ensure a significant increase in the growth of live mass and improve the chemical composition of meat, was assessed for different age groups. To solve this problem, the "Feed Optima Expert" optimization program has developed products of extruded feed. Food needs of canal som: 30 - 40 percent protein, 4 - 6 percent fat, no more than 5 percent fiber, 35 - 40 percent Nosazotic Extract substances and 12 - 13 thousand kilos of Joule digestible energy in 1 kilogram (in recalculation on dry matter).

Carbohydrate-Protein Interactions: Advances and Challenges.

A carbohydrate, also called saccharide in biochemistry, is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms. For example, sugars are low molecular-weight carbohydrates, and starches are high molecular-weight carbohydrates. Carbohydrates are the most abundant organic substances in nature and essential constituents of all living things. Protein-carbohydrate interactions play important roles in many biological processes, such as cell growth, differentiation, and aggregation. They also have broad applications in pharmaceutical drug design. In this review, we will summarize the characteristic features of protein-carbohydrate interactions and review the computational methods for structure prediction, energy calculations, and kinetic studies of protein-carbohydrate complexes. Finally, we will discuss the challenges in this field.

Исследования биохимических и микроструктурных особенностей щитовидной железы баранчиков специального откорма

Introduction. The present research featured biochemical and microstructural features of thyroid glands obtained from lambs raised on various feeds enriched with essential elements. The article focuses on iodine as the most important physiologically active microelement. Iodine participates in the synthesis of thyroid hormones, namely thyroxine and triiodothyronine, which are known to regulate metabolic processes. Iodine deficiency may impair reproductive function and cause such diseases as endemic goiter. Study objects and methods. The study involved thyroid glands from lambs of the Edilbaev breed aged seven months. The lambs were divided into four experimental groups, ten animals in each. The lambs received several feed additives. Ioddar-Zn and DAFS-25 had a balanced protein and carbohydrate content, while the mineral feed of Coretron brand contained such trace elements and minerals as iodine, selenium, and silicon. Results and discussion. The experiment made it possible to describe the microstructural profile of the thyroid glands extracted from seven-month-old lambs raised on feeds enriched with iodine and selenium. Ioddar-Zn and DAFS-25 did not harm the structure of the thyroid tissue, while causing its functional activation in some cases. The morphological parameters of the thyroid glands indicated some breed differences. The iodine concentration in the thyroid glands obtained from the experimental animals was five or six times higher than that in the control group. The content of mono- and diiodotyrosine depended on the accumulation profile of organic iodine. Conclusion. Diets enforced with DAFS-25, Ioddar-Zn, silicon, and a protein-carbohydrate complex produced no negative effect on the structure of the thyroid tissue. It fact, the diet increased the organic iodine content in the thyroid glands in the form of iodotyrosines. The gland structure revealed some cubic epithelium or follicular cells. The mass spectrometric studies confirmed the presence of covalently bound iodine in the form of mono- and diiodotyrosine. Thus, the abovementioned feed additives can be recommended for industrial use.

Morphological condition of the pulp of intact and affected by caries third molars

To date, there is a theory that increased resistance to caries is observed in the teeth, which for any reason underwent destructive changes in the pulp. That is why there is a need to study the impact of pulp vitality on the development of the carious process. The aim of the research was to study the microscopic structure of epoxy sections of intact and carious third molars. We studied 4 intact and 6 carious third molars. For this purpose, specimens were made taking into account the free penetration of the fixative solution into the pulp. To this end, immediately after the tooth was removed, we cut off its roots almost near the crown, preserving the integrity of the latter. The method relied on the impregnation of specimens with epoxy resin, according to the method of epoxy plastination of tooth specimens, developed at the Department of Human Anatomy of Ukrainian Medical Stomatological Academy. The epoxy blocks were cut with a disk into two halves until the hard tissues of the tooth crown were exposed together with the pulp. We found that the hard tissues (dentin and enamel coating) of intact third molars did not have any structural defects. However, their pulp chamber contained mainly an amorphous substance, devoid of any typical pulp tissue structures. That is, the pulp was in a state of complete devolution. Quite the opposite presentation was observed in specimens of carious teeth. We found that their pulp chamber contained quite noticeable tissue structures typical of the dental pulp. It is interesting that in the subodontoblastic layer, in front of the carious alteration of the enamel, there was compaction of the pulp, which may be due to infiltration of perivascular connective tissue by immunocompetent cells. It was found that on the border with carious destruction of enamel, there was a compacted spot of altered dentin, whose matrix was intensely pigmented in brown colour, due to the accumulation of melanin on the dentino-enamel junction. Its excessive formation is associated with the destruction of protein-carbohydrate complexes of organic matter in the deep layers of dentin. We found that the pulp compaction and the focus of carious alteration of the enamel are projectively connected by a radial cord of altered dentin, known in the literature as “dead tracts”. Hence, there is reason to believe that the identified changes indicate a latent form of caries, with a pulpogenic mechanism of development. Thus, it can be argued that the teeth, which for any reason underwent degenerative changes in the pulp, are not prone to carious lesions, whereas in carious teeth, the pulp is active and involved in the pathogenesis of the carious process.

Prediction of protein-carbohydrate complex binding affinity using structural features.

Protein-carbohydrate interactions play a major role in several cellular and biological processes. Elucidating the factors influencing the binding affinity of protein-carbohydrate complexes and predicting their free energy of binding provide deep insights for understanding the recognition mechanism. In this work, we have collected the experimental binding affinity data for a set of 389 protein-carbohydrate complexes and derived several structure-based features such as contact potentials, interaction energy, number of binding residues and contacts between different types of atoms. Our analysis on the relationship between binding affinity and structural features revealed that the important factors depend on the type of the complex based on number of carbohydrate and protein chains. Specifically, binding site residues, accessible surface area, interactions between various atoms and energy contributions are important to understand the binding affinity. Further, we have developed multiple regression equations for predicting the binding affinity of protein-carbohydrate complexes belonging to six categories of protein-carbohydrate complexes. Our method showed an average correlation and mean absolute error of 0.731 and 1.149kcal/mol, respectively, between experimental and predicted binding affinities on a jackknife test. We have developed a web server PCA-Pred, Protein-Carbohydrate Affinity Predictor, for predicting the binding affinity of protein-carbohydrate complexes. The web server is freely accessible at https://web.iitm.ac.in/bioinfo2/pcapred/. The web server is implemented using HTML and Python and supports recent versions of major browsers such as Chrome, Firefox, IE10 and Opera.

Comprehensive analysis of carbohydrate-protein recognition in the Protein Data Bank

Carbohydrate-protein interactions underpin wide-ranging aspects of biology. However, such interactions remain relatively unexplored in pharmaceutical and biotechnological applications, in part due to the challenges associated with their structural characterisation, both experimentally and computationally. Knowledge-based approaches have shown great success in the prediction of drug-protein and protein-protein interactions, although have not been comprehensively investigated for carbohydrate-protein interactions. In this work, carbohydrate-protein complexes from the Protein Data Bank were comprehensively obtained and analysed to identify patterns in how carbohydrate-protein interactions are mediated.

Assessment of the impact of new complex feed additives in the production of rabbit meat

Currently, there are a number of feed components that stimulate productivity, growth of animals and poultry. One of them is preparations of antioxidant action on the animal body, which have a positive effect on strengthening the immune system and increasing productivity. In this work, data are presented on the comparative effectiveness of feed additives of various nature: bioflavonoids, polysaccharides, organic acids and protein-carbohydrate complexes in the diets of young rabbits. In the animals of the experimental groups that received bioactive substances as part of the diets, positive dynamics was observed in terms of growth as well as immune status. The greatest effect on the formation of the productive qualities of young rabbits was exerted by the using of the additives Dihydroquercetin + Glimalask, the synergistic effect of which was manifested in the activation of metabolic processes in the body of growing animals.

The CH-π Interaction in Protein-Carbohydrate Binding: Bioinformatics and In Vitro Quantification.

The molecular recognition of carbohydrates by proteins plays a key role in many biological processes including immune response, pathogen entry into a cell, and cell-cell adhesion (e.g., in cancer metastasis). Carbohydrates interact with proteins mainly through hydrogen bonding, metal-ion-mediated interaction, and non-polar dispersion interactions. The role of dispersion-driven CH-π interactions (stacking) in protein-carbohydrate recognition has been underestimated for a long time considering the polar interactions to be the main forces for saccharide interactions. However, over the last few years it turns out that non-polar interactions are equally important. In this study, we analyzed the CH-π interactions employing bioinformatics (data mining, structural analysis), several experimental (isothermal titration calorimetry (ITC), X-ray crystallography), and computational techniques. The Protein Data Bank (PDB) has been used as a source of structural data. The PDB contains over 12 000 protein complexes with carbohydrates. Stacking interactions are very frequently present in such complexes (about 39 % of identified structures). The calculations and the ITC measurement results suggest that the CH-π stacking contribution to the overall binding energy ranges from 4 up to 8 kcal mol-1 . All the results show that the stacking CH-π interactions in protein-carbohydrate complexes can be considered to be a driving force of the binding in such complexes.

A systematic analysis of protein-carbohydrate interactions in the Protein Data Bank.

Protein-carbohydrate interactions underlie essential biological processes. Elucidating the mechanism of protein-carbohydrate recognition is a prerequisite for modeling and optimizing protein-carbohydrate interactions, which will help in discovery of carbohydrate-derived therapeutics. In this work, we present a survey of a curated database consisting of 6,402 protein-carbohydrate complexes in the Protein Data Bank (PDB). We performed an all-against-all comparison of a subset of nonredundant binding sites, and the result indicates that the interaction pattern similarity is not completely relevant to the binding site structural similarity. Investigation of both binding site and ligand promiscuities reveals that the geometry of chemical feature points is more important than local backbone structure in determining protein-carbohydrate interactions. A further analysis on the frequency and geometry of atomic interactions shows that carbohydrate functional groups are not equally involved in binding interactions. Finally, we discuss the usefulness of protein-carbohydrate complexes in the PDB with acknowledgement that the carbohydrates in many structures are incomplete.

ВЛИЯНИЕ МИНЕРАЛЬНЫХ УДОБРЕНИЙ НА ИЗМЕНЕНИЕ БИОХИМИЧЕСКОГО СОСТАВА ГЕТЕРОГЕННЫХ ПОСЕВОВ ЛЮЦЕРНЫ ИЗМЕНЧИВОЙ С МЯТЛИКОВЫМИ ТРАВАМИ НА СЕРЫХ ЛЕСНЫХ ПОЧВАХ ЦЕНТРАЛЬНОГО РЕГИОНА РОССИИ

Sustainable development of animal husbandry and feed production now can be characterized by a complex approach to the introduction of elements of intensive agricultural technologies, the main direction of which should be the rise of natural resource potential of agrocenoses and, as a result, achievement of the necessary amount of balanced carbohydrate-protein complex of highly nutritious feed. Until now, the structure of seeds of perennial grasses has been dominated mainly by bluegrass species. In the future, agricultural producers plan to expand the area of perennial grasses with an increase in the share of legume species in herbage mixtures. Perennial legumes in single and mixed sows are the main components in solving the problem of protein deficiency in the production of highly nutritious feeds. It is known that mixed (heterogeneous) sows of perennial legumes and bluegrass grasses have a clear advantage in productivity over single-species agrocenosis due to the fact that they are much more efficient in using nutrients from the soil and fertilizers, moisture, solar insolation due to the different structure of bush and root system of perennial grasses. When carrying out experiments in the fields of Bryansk SAU, a modern assortment of variable alfalfa and bluegrass perennial grasses was used. In herbage mixtures, the bean component varied from 40 to 50%. Seeding was carried out under the cover of annual ryegrass westerwold (Lolium westerwoldicum Wittm.), diploid variety Izorsky. As a legume component, we used variable alfalfa (Medicago varia Mart.). The bluegrass component is represented by the meadow Timothy (phlum pratense L.),meadow fescue (Festuca pratensis Huds.), cocksfoot(Dactylis glomerata L.), smooth brome (Bromopsis inermis Leyss.). at the present time, the introduction of modern science-based fertilizer systems and technologies for the cultivation of heterogeneous seeds based on the inclusion of crops with productive longevity in their composition will solve the problem of increasing production highly nutritious feed.

ProCaff: protein-carbohydrate complex binding affinity database.

Protein-carbohydrate interactions perform several cellular and biological functions and their structure and function are mainly dictated by their binding affinity. Although plenty of experimental data on binding affinity are available, there is no reliable and comprehensive database in the literature. We have developed a database on binding affinity of protein-carbohydrate complexes, ProCaff, which contains 3122 entries on dissociation constant (Kd), Gibbs free energy change (ΔG), experimental conditions, sequence, structure and literature information. Additional features include the options to search, display, visualization, download and upload the data. The database is freely available at http://web.iitm.ac.in/bioinfo2/procaff/. The website is implemented using HTML and PHP and supports recent versions of major browsers such as Chrome, Firefox, IE10 and Opera. gromiha@iitm.ac.in. Supplementary data are available at Bioinformatics online.

Gut Microbiota Modulation by Dietary Barley Malt Melanoidins.

Melanoidins are the final Maillard reaction products (protein–carbohydrate complexes) produced in food by prolonged and intense heating. We assessed the impact of the consumption of melanoidins from barley malts on gut microbiota. Seventy-five mice were assigned into five groups, where the control group consumed a non-melanoidin malt diet, and other groups received melanoidin-rich malts in increments of 25% up to 100% melanoidin malts. Feces were sampled at days 0, 1, 2, 3, 7, 14, and 21 and the microbiota was determined using V4 bacterial 16S rRNA amplicon sequencing and short-chain fatty acids (SCFA) by gas chromatography. Increased melanoidins was found to result in significantly divergent gut microbiota profiles and supported sustained SCFA production. The relative abundance of Dorea, Oscillibacter, and Alisitpes were decreased, while Lactobacillus, Parasutterella, Akkermansia, Bifidobacterium, and Barnesiella increased. Bifidobacterium spp. and Akkermansia spp. were significantly increased in mice consuming the highest melanoidin amounts, suggesting remarkable prebiotic potential.

RESEARCH OF MEDICAL AND BIOLOGICAL PROPERTIES OF SPECIALIZED PECTIN-CONTAINING MIXTURES IN THE ETHERAL CORRECTION OF THE TROPHOLOGICAL STATUS

Specialized pectin-containing mixtures have been developed to correct deficiency and underweight, represented by protein-carbohydrate complexes. The effectiveness of the use of ATP in complex therapy for the treatment of deficiency and underweight is proved.

Prospects for the use of protein-carbohydrate complex based on mung bean seeds in the functional meat products technology

The use of new non-traditional types of plant materials in the diet is one of the ways to improve the meat products’ quality. The combination of plant proteins with animals creates biologically active amino-acid complexes which increase its bioavailability for organism and biological value of the product. In this case, the use of non-traditional plant materials in the production technology of new types of sausage products to improve the quality of the end product is prospective and relevant. Research objective is development of formulations and technologies for new types of high biological value products, based on combination of meat raw materials with functional additives of plant origin. The work was performed at the Department of Food Technology FSBEI HE «Don State Agrarian University», Persianovsky, Rostov region. The objects of research were the new protein-carbohydrate complexes based on flour from germinated seeds of mung bean, control and model forcemeat based on trim beef of first grade, lean trim pork and mid fat trim pork, and end products. Introduction to the cooked sausage products formulation of mung bean germinated seeds flour has a beneficial effect on the organoleptic properties of the end product and enriches it with biologically valuable substances.

Influence of germination of wheat grain with selenium sources on the components of protein-carbohydrate complex

The aim of the study is histochemical identification of the components of protein-carbohydrate complex of wheat grains with selenium sources during germination. We formulated a hypothesis about the stimulating effect of 4.4-di [3 (5-methyldipirazolyl] selenid (DMDPS) on the biosynthesis of substances with a bactericidal effect, which include mucoid substances and glycoproteids in the composition of the components of the protein-carbohydrate complex. We confirm the hypothesis on histochemical identification of the components of the protein-carbohydrate complex of wheat grain during germination with sources of selenium. To identify acid mucopolysaccharides, transverse and longitudinal sections of the grain were stained with Alcian blue according to Steedman. Schiff-iodic acid revealed neutral glycoproteins and was clarified in xyllol. The sections were then placed into the balm and viewed in a Zeiss Axioscop 40 FX light microscope using a Levenhuk C 510 NG digital camera. To detect methionine, sections were stained with Schiff’s reagent; to identify cysteine (SH-groups), sections were treated with a 0.05% solution of 2.2-dioxy-6.6-dinaphthyl disulfide. The obtained images were analyzed using Photoshop CS 5 tools. Positive effect of wheat germination with DMDPA on the content of both neutral glycoproteids and mucopolysaccharides, with a direct correlation relationship, and on the content of methionine and cysteine was proved.

Technological Process of Germination of Wheat Grain under the Water Tincture of Aloe and ITS Physical-Chemical Properties

Germination of wheat grain promotes the transition of hardly digestible nutrients into an easily accessible form with increasing the amount of vitamins and minerals. This paper presents the technological process of wheat grain germination under the water tincture of aloe. The germinating power and ability of wheat grain grown in 25% solution of water tincture of aloe are 95% and 95%, respectively. The analysis of the data shows that the amount of all nutrients decreases, since the destruction of the protein-carbohydrate complex. The activity of enzymes increases, and the cellular destruction of the endosperm occurs. Carbohydrates reduction is associated with intensive grain respiration. Germination is also associated with a decrease in fat from 2.45% to 1.25%.

ANALYSIS OF THE CONNECTIVE TISSUE COMPONENTS IN THE ORAL FLUID OF CHILDREN SUFFERING FROM CHRONIC CATARRHAL GINGIVITIS UNDER CONDITIONS OF DIFFUSE SIMPLE GOITER

Objective - to study changes of the quantitative and qualitative content of the proteincarbohydrate complexes in the oral fluid of children suffering from chronic catarrhalgingivitis (CCG).Material and methods. 85 children aged 12-15 years were examined. Two groups of observation were formed: I group - somatically healthy children (40 individuals); II group -children with diffuse simple goiter (DSG) (45 individuals). Subgroups were isolatedwithin every group depending on availability or lack of differences in patients with CCG:ІА - somatically and stomatologically healthy children (n=20); ІB - somatically healthychildren with CCG (n=20); ІІА - children with DSG without lesions of the periodontaltissues (n=22); ІІB - children with DSG and CCG (n=23). Oral fluid was used for paraclinical examination. The whole protein level, glycoprotein concentration, hexosaminecontent, the level of fucose and sialic acids were used.Results. When inflammatory process develops in the gums, an average level of protein inthe oral fluid 60% increases and it is (3,39±0,24) g/L. In case somatic pathology joins theprotein level increases considerably. At the same time, the content of proteincarbohydrate complexes several times decreases. The protein level increases significantlyunder conditions of somatic pathology joining.Contrary to the changes of amino sugars concentration in the oral fluid of children fromthe experimental groups, the level of terminal carbohydrate glycoprotein residuesincreases, which is indicative of disorders of the saliva protector properties.Conclusions. 1. Glycoprotein level decreases in the oral fluid of children with CCGagainst a background of an increased protein level. These changes intensify with comorbid DSG, which may be indicative of a partial breakdown of protectiveaminopolysaccharides performing a protective saliva function. 2. A reliable decrease ofhexosamines in the oral fluid of children with both CCG and thyroid pathology is found,which correlates with an increased level of terminal carbohydrate residues - sialic acidsand fucose, and is indicative of disorders in glycoprotein synthesis in the glandularstructures.

ProCarbDB: a database of carbohydrate-binding proteins.

Carbohydrate-binding proteins play crucial roles across all organisms and viruses. The complexity of carbohydrate structures, together with inconsistencies in how their 3D structures are reported, has led to difficulties in characterizing the protein–carbohydrate interfaces. In order to better understand protein–carbohydrate interactions, we have developed an open-access database, ProCarbDB, which, unlike the Protein Data Bank (PDB), clearly distinguishes between the complete carbohydrate ligands and their monomeric units. ProCarbDB is a comprehensive database containing over 5200 3D X-ray crystal structures of protein–carbohydrate complexes. In ProCarbDB, the complete carbohydrate ligands are annotated and all their interactions are displayed. Users can also select any protein residue in the proximity of the ligand to inspect its interactions with the carbohydrate ligand and with other neighbouring protein residues. Where available, additional curated information on the binding affinity of the complex and the effects of mutations on the binding have also been provided in the database. We believe that ProCarbDB will be an invaluable resource for understanding protein–carbohydrate interfaces. The ProCarbDB web server is freely available at http://www.procarbdb.science/procarb.

Development of highly efficient technology of grain moisture-heat treatment and the design of conditioner steamer

As a result of the conducted experimental studies, the main kinetic regularities of the steaming process under investigation were determined and the choice of rational modes of grain moisture-heat treatment was validated: steaming of barley and wheat with steam to a moisture content of 19 % at a steam consumption of 100–180 kg/h and a pressure of 0.20–0.35 MPa for 10–12 minutes, and corn – for 15–16 minutes. These developed modes provide the best conditions for the thermomechanical destruction of the protein-carbohydrate complex in order to increase its availability to digestive enzymes and increase the digestibility of starch, do not reduce the digestibility of protein and improve sanitary condition. A method of engineering calculation was developed, which formed the basis for the creation of an original design of conditioner steamer. The performed constructive calculation included the calculation of the mixer-humidifier, the calculation of the jet nozzle and the determination of the dispersed characteristics during steam atomization, as well as the thermal calculation of the conditioner steamer, which made it possible to determine the steam consumption and determine the rational heating temperature of the grains and their moisture content. A distinctive feature of the conditioner steamer is a higher productivity due to the significant acceleration of diffusion process of moisture into grains; the possibility of improving the quality by increasing the degree of starch gelatinization due to selected technological steaming modes.

Moisture diffusivity in concentrated and dry protein-carbohydrate films

Understanding moisture diffusivity behaviour over a wide range of moisture contents is pivotal for optimising drying operations. Generally, data on moisture diffusivity are scarce and the effect of matrix composition on moisture diffusivity at relevant temperature for drying processes is not yet well described. In this paper moisture diffusivity in protein-carbohydrate films is systematically investigated for a wide range of moisture contents at 80 °C.Diffusion data are obtained from controlled thin film drying experiments following the regular regime method and compared to theoretical models. Moisture diffusivity for binary maltodextrin-water and whey protein-water systems appeared similar and were reasonably well described with the Darken relation. Diffusivity was lower for casein-water systems at moisture contents above 0.15 kg water/kg, which may be explained by compartmentalization of water in the casein micelles. At low moisture contents all binary systems showed universal behaviour, which may be explained by random coil behaviour leading to similar water-molecule interactions. This behaviour could be well described by free-volume theory. In mixed systems of proteins and carbohydrates moisture diffusivity appeared strongly influenced by the presence of casein, probably due to their high voluminosity. Finally, it was surprisingly observed that diffusivity in multicomponent systems decreased sharply at lower water contents when compared to binary systems. This might be explained by a denser molecular packed system in the dry regime for multicomponent systems or water trapping by protein-carbohydrate complexes.