Amino Acids Tyr Research Articles

The Effect of Semen Cryopreservation Process on Metabolomic Profiles of Turkey Sperm as Assessed by NMR Analysis.

Simple SummarySemen cryobanking is a valuable tool for preserving the genetic resources of a wide range of species, providing the opportunituy to preserve representative samples and reconstruct the population or diversity. However, in avian species, the freezing–thawing process results in a sharp reduction in sperm quality and consequently fertility. This is mainly due to the lack of knowledge about the molecular basis of the cryopreservation process, especially in more sensitive species such as turkey. Thus, in this study, we took advantage of NMR technology to assess the changes in metabolic profile occurring in turkey sperm cryopreservation, which were correlated with sperm qualitative parameters measured in both fresh and frozen–thawed samples. Hence, the results reported here depict a clearer scenario about the changes in the levels of amino acids, other water-soluble compounds, and lipids resulting from the freezing–thawing process. Moreover, a wide discussion about the possible pathway affected by cryopreservation is provided. Therefore, this study allows us to: (i) identify biological markers related to the sperm freezability of male turkey donators; (ii) suggest a supplementation of specific metabolites in the diet or in the freezing medium in order to obtain spermatozoa abler to withstand the freezing process.Semen cryopreservation represents the main tool for preservation of biodiversity; however, in avian species, the freezing–thawing process results in a sharp reduction in sperm quality and consequently fertility. Thus, to gain a first insight into the molecular basis of the cryopreservation of turkey sperm, the NMR-assessed metabolite profiles of fresh and frozen–thawed samples were herein investigated and compared with sperm qualitative parameters. Cryopreservation decreased the sperm viability, mobility, and osmotic tolerance of frozen–thawed samples. This decrease in sperm quality was associated with the variation in the levels of some metabolites in both aqueous and lipid sperm extracts, as investigated by NMR analysis. Higher amounts of the amino acids Ala, Ile, Leu, Phe, Tyr, and Val were found in fresh than in frozen–thawed sperm; on the contrary, Gly content increased after cryopreservation. A positive correlation (p < 0.01) between the amino acid levels and all qualitative parameters was found, except in the case of Gly, the levels of which were negatively correlated (p < 0.01) with sperm quality. Other water-soluble compounds, namely formate, lactate, AMP, creatine, and carnitine, turned out to be present at higher concentrations in fresh sperm, whereas cryopreserved samples showed increased levels of citrate and acetyl-carnitine. Frozen–thawed sperm also showed decreases in cholesterol and polyunsaturated fatty acids, whereas saturated fatty acids were found to be higher in cryopreserved than in fresh sperm. Interestingly, lactate, carnitine (p < 0.01), AMP, creatine, cholesterol, and phosphatidylcholine (p < 0.05) levels were positively correlated with all sperm quality parameters, whereas citrate (p < 0.01), fumarate, acetyl-carnitine, and saturated fatty acids (p < 0.05) showed negative correlations. A detailed discussion aimed at explaining these correlations in the sperm cell context is provided, returning a clearer scenario of metabolic changes occurring in turkey sperm cryopreservation.

Investigation of Metabolic Resistance to Soybean Aphid (Aphis glycines Matsumura) Feeding in Soybean Cultivars.

Simple SummaryThis project examined the interaction between soybean aphids and Ontario-grown soybean cultivars to determine which leaf metabolites were most associated with aphid resistance. Tolerance and resistance were determined by measuring the growth and reproduction of aphids and leaf feeding damage over 10-day and 4-week infestation periods. Chromatographic techniques were used for the analysis of legume-specific plant natural products and isoflavonoids, and high-resolution mass spectrometry was used for the identification of free amino acids in aphid-resistant, tolerant, and susceptible soybean cultivars. There was a low correlation between isoflavonoid leaf concentrations and aphid resistance in the soybean varieties studied; however, the aphid-resistant cultivars were determined to have lower free amino acid concentrations, indicating that lower nutrient quality could be responsible for the resistance observed. Identifying these cultivars is important for managing aphid populations and provides an additional tool for soybean integrated pest management.Soybean aphid (Aphis glycines) is a major soybean (Glycine max) herbivore pest in many soybean growing regions. High numbers of aphids on soybean can cause severe reductions in yield. The management of soybean aphids includes monitoring, insecticide applications when required, and the use of resistant cultivars. Soybean aphid-resistant soybean varieties are associated with genes that confer one or more categories of resistance to soybean aphids, including antibiosis (affects survival, growth, and fecundity), antixenosis (affects behaviour such as feeding), and tolerance (plant can withstand greater damage without economic loss). The genetic resistance of soybean to several herbivores has been associated with isoflavonoid phytoalexins; however, this correlation has not been observed in soybean varieties commonly grown in southern Ontario, Canada. Isoflavonoids in the leaves of 18 cultivars in the early growth stage were analyzed by HPLC and the concentration by fresh weight was used to rate the potential resistance to aphids. Greenhouse and growth cabinet trials determined that the cultivars with greater resistance to aphids were Harosoy 63 and OAC Avatar. The most susceptible cultivar was Maple Arrow, whereas Pagoda and Conrad were more tolerant to aphid feeding damage. Overall, there was a low correlation between the number of aphids per leaf, feeding damage, and leaf isoflavonoid levels. Metabolite profiling by high-resolution LC-MS determined that the most resistant cultivar had on average lower levels of certain free amino acids (Met, Tyr, and His) relative to the most susceptible cultivar. This suggests that within the tested cultivars, nutritional quality stimulates aphid feeding more than isoflavonoids negatively affect aphid feeding or growth. These findings provide a better understanding of soybean host plant resistance and suggest ways to improve soybean resistance to aphid feeding through the breeding or metabolic engineering of leaf metabolites.

Inhibition Plcγ2 and Hydrophobic Acids Synthesis cause Osteoarthritis, Diabetes and C-lymphocytic Leukemia Diseases Where Normally PLCs can Recover Interferons Synthesis

Proper S6K regulate BTK pathways which regulate PLCγ2 synthesis which are main regulations for thromboxane-A “TXA2” synthesis, and necessary for B-cell maturations and T-cells modulations and functions. Deficiency in Ser amino acids and in hydrophobic amino acids are reflect decreasing in synthase enzyme lead to deficiency in BTK function and deficiency in PLCγ2 that lead increasing in colony stimulating Factor-1 “CSF-1 where PLCγ1 specified to circuit to CSF-1 which upon synthase effect will promote PLCγ2 synthesis which necessary for activating BCRs for activating both IgM and IgD antigen for B-cells maturation and activities, for T-cells modulations, and for TXA2 synthesis. Proper Akt, S6K1 synthesis, OPA1 enzymes and fatty Acyl-COAs are necessary for regulating RORs isoforms Biosynthesis which regulate both IFNs and PLCs synthesis {Where both IFNs and PLCs are covering each other (IFNs &lt;¬&gt;PLCs) } that PLCγ1 promote the PLCγ2 synthesis upon BTK regulations. Osteoarthritis “OA” is characterized by a sharp expression in Gamma-Phospholipase C-1 “PLCγ1”, with decreasing “or inhibition” in PLCγ2 which reflect decreasing in synthase functions and in IFN-beta synthesis that reflect decreasing or deficiency in TXA2 Biosynthesis. The increasing in PLCγ1 with Deficiency in Ser amino acids will lead to deficiency in Ser phosphorylation signaling and deficiency in the pyrimidine kinases (PST-thymine and PS T-Cytosine kinases) synthesis, that lead to decreasing in synthase activity which will reflect down regulations in BTK pathways and inhibition in PLCγ2 productions which will reflect diabetes ( production of Androgen instead of estrogen), and can reflect Osteoarthritis “OA” prognosis which depend on the percentage of Deficiency or inhibition in basic amino acids and their basic necessary signaling pathways. T2DM is strongly connected with OA diseases and are linked together by the deficiency in Ser amino acids and their phosphorylation, and any early decreasing in Ser and in hydroponic acids synthesis can lead to both and more disease. Pathogenic type 2 diabetes associated with progressive beta-cell impairment due to the mutations in the production of S6K1 (deficiency in Ser ”TCT, TCC,TCA”), and inhibition in the PLCγ2 which due to inhibition or decreasing in Synthase and lead to deficiency in BCR activities. The decreasing in PS/T-Thymine Kinases and PS/T-Cytosine kinases chains (mTORC1) due to deficiency in Ser amino acids (where normally those pyrimidine kinases are produced from the phosphorylation process on Ser amino acids) will lead to mutated S6K and Akt productions and decreasing or mutations in ATPase and GTPase which lead to decreasing in OPA1 repair and lead to synthesis of Androgen instead of Estrogen which are depending on the availability of hydrophobic amino acids synthesis including Ser and Tyr amino acids. The effect of Synthetase enzymes on biological molecules is for creating active gamma-subunits “PLCγ1” that can be modified by synthase effect for Betasubunit synthesis “PLCγ2” then will be modified by phospholipase effects for alpha subunits productions. The releasing of pyrimidine kinases “PS/T-Thymine -Kinase and PS/T-Cytosine -kinase chains (mTORC1)” are so necessary steps for proper S6K productions and for proper fatty Acyl-COAs synthesis (long fatty AcylCOA) which are so important for regulating RORs Biosynthesis and necessary for both IFNs and for PLCs productions which started by the productions of PLC-gamma and IFN gamma, where both PLCγ1 and IFN-Gamma are necessary for regulating proper PLCγ2 biosynthesis upon “BTK activity” then PLCγ2 are necessary for regulating BCR functions which imp for regulating both IgM and IgD activities for B-cell maturations, for adjusting anti-inflammatory processes and for T-cells modulations, then PLCγ2 is so necessary for thromboxane-A synthesis, and for bone growth and immune modulations. Deficiency in conversion of glutarate to glutamate and decreasing in Proline (hydroponic acids) biosynthesis can affect on Cartilage synthesis and bone growth due to decreasing in stimulating mitochondrial OPA1 oxidations. Protein tyrosine phosphatase (PTP) gamma (carry−ve charge regulated firstly by synthetase gamma-oxidations) has been proposed to be an important regulator for chondrogenic patterning, where PTPs are critical regulators of tyrosine phosphorylation that it’s activity depends on the Tyr, and Ser synthesis (during hydrophobic acids synthesis ) and on JAK state signaling activities. And so, the proline-rich tyrosine kinases regulate proper PLCs isoforms which compete for binding site at the very C terminus of fibroblast growth factor for osteorogenitor embryonic development, and bone growth.

A Modular Synthesis of Teraryl-Based α-Helix Mimetics, Part 3: Iodophenyltriflate Core Fragments Featuring Side Chains of Proteinogenic Amino Acids.

Teraryl‐based α‐helix mimetics have proven to be useful compounds for the inhibition of protein‐protein interactions (PPI). We have developed a modular and flexible approach for the synthesis of teraryl‐based α‐helix mimetics using a benzene core unit featuring two leaving groups of differentiated reactivity in the Pd‐catalyzed cross‐coupling used for teraryl assembly. In previous publications we have introduced the methodology of 4‐iodophenyltriflates decorated with the side chains of some of the proteinogenic amino acids. We herein report the core fragments corresponding to the previously missing amino acids Arg, Asn, Asp, Met, Trp and Tyr. Therefore, our set now encompasses all relevant amino acid analogues with the exception of His. In order to be compatible with the triflate moiety, some of the nucleophilic side chains had to be provided in a protected form to serve as stable building blocks. Additionally, cross‐coupling procedures for the assembly of teraryls were investigated.

DLPacker: Deep learning for prediction of amino acid side chain conformations in proteins.

Prediction of side chain conformations of amino acids in proteins (also termed "packing") is an important and challenging part of protein structure prediction with many interesting applications in protein design. A variety of methods for packing have been developed but more accurate ones are still needed. Machine learning (ML) methods have recently become a powerful tool for solving various problems in diverse areas of science, including structural biology. In this study, we evaluate the potential of deep neural networks (DNNs) for prediction of amino acid side chain conformations. We formulate the problem as image-to-image transformation and train a U-net style DNN to solve the problem. We show that our method outperforms other physics-based methods by a significant margin: reconstruction RMSDs for most amino acids are about 20% smaller compared to SCWRL4 and Rosetta Packer with RMSDs for bulky hydrophobic amino acids Phe, Tyr, and Trp being up to 50% smaller.

Antidiabetic Formulation Development Based on Natural Materials As α-Glucosidase Enzyme Inhibitor

Salam (Syzygium polyanthum), stevia (Stevia rebaudiana), tea (Camellia sinensis), and yakon (Smallanthus sonchifolius) leaves act as inhibitors of the α-glucosidase enzyme. The aims of this research were to (i) determine the best combination of polyherbals that could inhibit the α-glucosidase enzyme, (ii) determine the phytochemical content of the teraactive fraction, and (iii) predict potential bioactive compounds that were responsible for the inhibition of the α-glucosidase enzyme. The novelty of this research was its use of several types of herbs, combined with various compositions, to obtain the IC50 value. Also, this research predicted the activity of the compound through a molecular docking approach with Molegro Virtual Docker software. The extraction was carried out with the maceration method with 96% ethanol and then partitioned with ethyl acetate and water. Two fractions with high inhibition percentages were combined with a ratio of 1:1, 1:2, 2:1, 1:3, and 3:1, and they were tested against the α-glucosidase inhibitory enzyme. The best fraction was identified for chemical compound content by Liquid Chromatography Mass Spectroscopy (LC-MS/MS). The compounds were analyzed in silico by using Molegro Virtual Docker software, which obtained the best reranc score. The results showed that the ethanol extract of tea leaves had the highest activity, at 65.51%, and salam, stevia, and yakon leaves had inhibition percentages of 44.11%, 34.74%, and 28.85%, respectively. The combination of water fractions of tea and salam leaves had the best activity at a ratio of 3:1 with IC50 of 16.53 ppm, which was almost equivalent to acarbose as a positive control with IC50 of 14.62 ppm. The analysis of LC-MS/MS for the water fraction of tea contained nicotiflorin with m/z 594, a reranc score of -118.24, and amino acid residues Arg, Asp, Asn, Cys, Glu, His, Thr, and Tyr. The water fraction of salam leaves contained quercetagetin with m/z 319, the reranc score was –89.123, and the amino acid residues Asn, Asp, Gln, Lys, Phe, Pro, Thr, and Trp.

Uncovering the Role of PhzC as DAHP Synthase in Shikimate Pathway of Pseudomonas&nbsp;chlororaphis HT66.

Simple SummaryThis study investigated PhzC, one essential 3-Deoxy-D-arabino-heptulosnate-7-phosphate (DAHP) synthase that catalyzes the first step of the shikimate pathway in Pseudomonas chlororaphis. We identified and characterized phzC, which is different from the reported DAHP synthase encoding genes aroF, aroG and aroH in E. coli. PhzC accounts for approximately 90% of the total DAHP synthase activities in P. chlororaphis and it plays the most critical role in four DAHP synthases in the shikimate pathway. Moreover, the results showed that phzC in P. chlororaphis HT66 is not sensitive to feedback inhibition. This study demonstrated that PhzC is essential for phenazine-1-carboxamide (PCN) biosynthesis without inhibition in feedback by PCN production. It highlighted the importance of PhzC and applying P. chlororaphis for shikimate pathway-derived high-value biological production.DAHP synthase catalyzes the first step in the shikimate pathway, deriving the biosynthesis of aromatic amino acids (Trp, Phe and Tyr), phenazine-1-carboxamide, folic acid, and ubiquinone in Pseudomonas chlororaphis. In this study, we identified and characterized one DAHP synthase encoding gene phzC, which differs from the reported DAHP synthase encoding genes aroF, aroG and aroH in E. coli. PhzC accounts for approximately 90% of the total DAHP synthase activities in P. chlororaphis HT66 and plays the most critical role in four DAHP synthases in the shikimate pathway. Inactivation of phzC resulted in the reduction of PCN production by more than 90%, while the absence of genes aroF, aroG and aroH reduced PCN yield by less than 15%, and the production of PCN was restored after the complementation of gene phzC. Moreover, the results showed that phzC in P. chlororaphis HT66 is not sensitive to feedback inhibition. This study demonstrated that gene phzC is essential for PCN biosynthesis. The expression level of both phzC and phzE genes are not inhibited in feedback by PCN production due to the absence of a loop region required for allosteric control reaction. This study highlighted the importance of PhzC and applying P. chlororaphis for shikimate pathway-derived high-value biological production.

Virtual investigation of the biomass conversion efficiency of three Streptomyces species

Global worries about the gradual depletion of the non-renewable fossil fuel reserves, as well as the problem of environmental pollution, and global warming have prompted researchers to opt for more sustainable and environmentally friendly solutions. Converting biomass to bioethanol is a cost effective and inexpensive alternative to produce energy. The lytic polysaccharide monooxygenase (LPMO) enzyme of microbial origin represents an ideal solution because of their catalytic potential for the cleavage of the cellulosic biomass and the production of simple fermentable sugars. Here, we have described the 3D structures, the molecular functioning, as well as the cellulosic biomass conversion efficiency of three LPMOs belonging to three species of Streptomyces, S. albidoflavus, S. flaveus, and S. griseus. Analysis of the conserved domains of the amino acid sequences showed that the three enzymes belong to the LPMO-10 family and include an LPMO domain and a carbohydrate-binding domain. The enzyme of the species S. griseus further comprises two cellulose binding domain and cellulase/cellobiase CelA1 (Carbohydrate transport and metabolism) domain. Homology modeling of the 3D structures of the three enzymes was carried out by the SwissModel program, the models are then checked and validated. The analysis of the interactions at the active site level of the three modeled LPMOs showed the presence of conserved amino acids in all the studied enzymes, specially the His-His brace located around the copper ion. The result of the molecular docking with the cellotetraose substrate shows very close binding energies for the three LPMOs (-5.5 kcal/mol for S. griseus, and −5.3 kcal/mol for S. albidoflavus and S. flaveus) indicating the same affinities of these enzymes to the cellulosic substrates. The visualization of the interactions of cellotetraose within the catalytic sites of the enzymes showed the involvement of the amino acids His, Ala, Trp, Tyr, Phe, and Glu, which are well conserved in the two LPMOs of S. griseus and S. albidoflavus species suggesting a C1 oxidizing activity, whereas for the LPMO of S. flaveus, the Phe and Glu are replaced by Tyr and Gln, respectively suggesting a C1/C4 oxidizing AA10. The molecular information obtained during this study confirms the cellulose degradation potential of Streptomyces LPMOs, as well as their different modes of cellulose oxidation and provides strong evidence of the interest of these enzymes in the biomass conversion.

Characteristics of Collagen Preparations from Leather Wastes by the High Pressure Liquid Chromatography Method

The raw trimming waste from the leather industry is considered potential hazardous waste as a consequence of the chrome tanned leather process. On the other hand, leather waste contains a large amount of precious protein – collagen, which has many uses. Nowadays, collagen preparations obtained from leather waste are available on the market. This paper presents a procedure for the determination of amino acids in five collagen preparations of animal origin. Recent improvements in HPLC-based methods for analysing amino acids have made it feasible to analyse different sample types accurately. In this study the 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatization procedure was applied. The amino acid analysis indicated the presence of 18 amino acids (Asp, Ser, Glu, His, Gly, Arg, Thr, Ala, Pro, Cys, Tyr, Val, Lys, Met, Ile, Leu, Phe and Hyp) in the collagen samples. Glycine, alanine, proline and hydroxyproline were the most abundant amino acid, whereas the lowest contents corresponded to serine, tyrosine, valine and izoleucine. The analysis proposed can be used with confidence in collagen quality control to guarantee appropriate amino acid content.

Effects of Multi-Bacteria Solid-State Fermented Diets with Different Crude Fiber Levels on Growth Performance, Nutrient Digestibility, and Microbial Flora of Finishing Pigs.

Simple SummaryDietary cellulase was found to be an important nutrient, and solid-state fermentation could improve the nutritional value of feed. To study the effects of multi-bacteria solid-state fermented diets and dietary crude fiber levels on finishing pigs, a total of 36 pigs were divided into four treatments: (1) pigs fed a basal diet containing 7.00% CF (HF), (2) pigs fed a basal multi-bacteria fermentation diet containing 7.00% CF (HFM), (3) pigs fed a basal diet containing 2.52% CF (LF), and (4) piglets fed a basal multi-bacteria fermentation diet containing 2.52% CF (LFM). The growth performance, nutrient digestibility and digestion amount, serum biochemical index, and fecal microflora were evaluated. Multi-bacteria solid-state fermentation had a positive effect on the nutrient digestion and serum biochemical indicators, which was contrary to high-fiber diets. Both high-fiber diets and multi-bacteria solid-state fermentation could optimize intestinal flora in finishing pigs.This study aimed to investigate the effects of multi-bacteria solid-state fermented diets with different crude fiber (CF) levels on growth performance, nutrient digestibility, and microbial flora of finishing pigs. The multi-bacteria solid-state fermented diets were made up of Lactobacillus amylovorus, Enterococcus faecalis, Bacillus subtilis, and Candida utilis. According to a 2 (factors) × 2 (levels) design, with the two factors being multi-bacteria solid-state fermentation (fed non-fermented diet or multi-bacteria fermentation) or CF levels (fed a basal diet containing 2.52% CF or 7.00% CF), a total of 36 finishing pigs (70.80 ± 5.75 kg) were divided into 4 treatments with 9 barrows per group: (1) pigs fed a diet containing 7.00% CF (HF), (2) pigs fed a multi-bacteria fermentation diet containing 7.00% CF (HFM), (3) pigs fed a diet containing 2.52% CF (LF), and (4) piglets fed a multi-bacteria fermentation diet containing 2.52% CF (LFM). This experiment lasted 28 days. The multi-bacteria solid-state fermented diet increased the backfat thickness (p < 0.05) and apparent total tract nutrient digestibility (ATTD) of CF, neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), 8 amino acids (Trp, Asp, Gly, Cys, Val, Met, Ile, and Leu), total essential amino acids (EAA), total non-essential amino acids (NEEA), and total amino acids (TAA) (p < 0.05). Multi-bacteria solid-state fermented diet increased serum concentrations of HDL-c, ABL, TP, and GLU, the serum enzyme activities of GSH-Px, T-AOC, SOD, and CAT (p < 0.05), the relative abundance of Lactobacillus, Oscillospira, and Coprococcus (p < 0.05), and the abundance of YAMINSYN3-PWY, PWY-7013, GOLPDLCAT-PWY, ARGORNPROST-PWY, and PWY-5022 pathways (p < 0.05). The multi-bacteria solid-state fermented diet reduced the digestion amount of CF, NDF, and ADF (p < 0.05), the serum concentrations of TC, TG, LDL-c, BUN, and MDA (p < 0.05), the relative abundance of Streptococcaceae (p < 0.05), and the abundance of PWY-6470, PWY0-862, HSERMETANA-PWY, LACTOSECAT-PWY, MET-SAM-PWY, PWY-6700, PWY-5347, PWY0-1061, and LACTOSECAT-PWY pathways (p < 0.05). The high-fiber diet increased average daily feed intake (p < 0.05), the serum concentrations of TC, TG, LDL-c, BUN, and MDA (p < 0.05), the relative abundance of Clostridiaceae_Clostridium and Coprococcus (p < 0.05), and the abundance of TCA-GLYOX-BYPASS, GLYCOLYSIS-TCA-GLYOX-BYPASS, and PWY-6906 pathways (p < 0.05). The high-fiber diet reduced chest circumference (p < 0.05) and ATTD of ether extract (EE), CF, NDF, ADF, Ca, CP, 18 amino acids (Trp, Thr, Val, Met, Ile, Leu, Phe, Lys, His, Arg Asp, Ser, Glu, Gly, Ala, Cys, Tyr, and Pro), EAA, NEAA, and TAA (p < 0.05). The high-fiber diet also reduced the serum concentrations of HDL-c, TP, ABL, and GLU, the serum enzyme activities of T-AOC, GSH-Px, SOD, and CAT (p < 0.05), and the relative abundance of Akkermansia and Oscillospira (p < 0.05). There was no significant effect of the interaction between multi-bacteria fermentation and dietary CF levels, except on the digestion amount of CF (p < 0.05). The 7.00% CF had a negative effect on the digestion of nutrients, but multi-bacteria solid-state fermentation diets could relieve this negative effect and increase backfat thickness. High-fiber diets and multi-bacteria solid-state fermentation improved the diversity and abundance of fecal microorganisms in finishing pigs.

Genetic effect on free amino acid contents of egg yolk and albumen using five different chicken genotypes under floor rearing system.

Chicken eggs play an important role as food resources in the world. Although genetic effects on yolk and albumen contents have been reported, the number of chicken genotypes analyzed so far is still limited. To investigate the effect of genetic background on 10 egg traits, 19 yolk amino acid traits, and 19 albumen amino acid traits, we evaluated a total of 58 eggs from five genotypes: two Japanese indigenous breeds (Ukokkei and Nagoya) and three hybrids (Araucana cross, Kurohisui, and Boris Brown) under a floor rearing system. One-way ANOVA revealed significant effects of genotype on 10 egg traits, 8 yolk amino acids (Asp, Glu, Ser, Gly, Thr, Tyr, Cys, and Leu), and 11 albumen amino acids (Asp, Glu, Asn, Ser, Gln, His, Ala, Tyr, Trp, Phe, and Ile) contents. Moderate to strong positive phenotypic correlations among traits within each trait category (size and weight traits, yolk amino acid traits, and albumen amino acid traits), whereas there were basically no or weak correlations among the trait categories. However, a unique feature was found in the Araucana cross indicating moderate positive correlations of amino acids between yolk and albumen. These results suggest that genetic factors can modify not only the size and weight of the egg and eggshell color but also yolk and albumen free amino acids contents.

A Targeted Serum Metabolomics GC-MS Approach Identifies Predictive Blood Biomarkers for Retained Placenta in Holstein Dairy Cows.

The retained placenta is a common pathology of dairy cows. It is associated with a significant drop in the dry matter intake, milk yield, and increased susceptibility of dairy cows to metritis, mastitis, and displaced abomasum. The objective of this study was to identify metabolic alterations that precede and are associated with the disease occurrence. Blood samples were collected from 100 dairy cows at −8 and −4 weeks prior to parturition and on the day of retained placenta, and only 16 healthy cows and 6 cows affected by retained placenta were selected to measure serum polar metabolites by a targeted gas chromatography–mass spectroscopy (GC-MS) metabolomics approach. A total of 27 metabolites were identified and quantified in the serum. There were 10, 18, and 17 metabolites identified as being significantly altered during the three time periods studied. However, only nine metabolites were identified as being shared among the three time periods including five amino acids (Asp, Glu, Ser, Thr, and Tyr), one sugar (myo-inositol), phosphoric acid, and urea. The identified metabolites can be used as predictive biomarkers for the risk of retained placenta in dairy cows and might help explain the metabolic processes that occur prior to the incidence of the disease and throw light on the pathomechanisms of the disease.

Maduración postcosecha de Pouteria lucuma: Efecto de las condiciones de almacenamiento en los componentes fisicoquímicos, metabolitos y capacidad antioxidante e hipoglucemiante

Inadequate storage conditions can affect the sensory, physicochemical, and functional properties of tropical fruits such as Pouteria lucuma; which is a climacteric fruit, with a pleasant aroma and flavor; Peru being the main producer and exporter of this fruit, postharvest storage conditions have not been studied to maintain its properties. The objective of the research was to evaluate the effect of the storage conditions on the main physicochemical components, primary and secondary metabolites, antioxidant, and hypoglycemic capacity during postharvest ripening, under two storage conditions: ambient (29 °C and 70% RH) and climatic chamber (15 °C and 90% RH). Regarding the physicochemical characteristics, the state of maturity influenced acidity, pH, reducing sugars, starch, dietary fiber, firmness, pulp color and epicarp. In climate-controlled storage, glucose is the only metabolite that increases; while fructose, alcohol sugars and amino acids (Ala and Val), present higher values ​​under ambient conditions; sucrose, organic acids, amino acids (Tyr, Glu, Asp and Thr), β-carotene, total phenolic compounds and total carotenoids were not affected by the type of storage. The measure of antioxidant and hypoglycemic capacity decreased significantly (p &lt; 0,05), showing to be affected only by the state of maturity. The study of the carotenoid profile according to its spectrum (UV-vis) showed the presence of the group of xanthophylls. The results indicate that the state of maturity concerning the storage condition influenced most of the changes studied.

Probing the biological toxicity of pyrene to the earthworm Eisenia fetida and the toxicity pathways of oxidative damage: A systematic study at the animal and molecular levels

Pyrene (Pyr), a widely used tetracyclic aromatic hydrocarbon, enters soil in large quantities and causes environmental pollution due to its production and mining. In order to systematically study the biotoxicity of pyrene to model organisms Eisenia fetida in soil, experiments were carried out from four dimensions: animal, tissue, cell and molecule. Experimental results proved that the mortality rate increased with increasing concentration and time of exposure to pyrene, while the mean body weight and spawning rate decreased. Meanwhile, when the pyrene concentration reached 900 mg/kg, the seminal vesicle and longitudinal muscle of the earthworm showed obvious atrophy. Experimental results at the cellular level showed that pyrene induced cell membrane damage and Ca2+ influx triggered mitochondrial membrane depolarization and a surge in ROS levels. Oxidative stress causes damage to proteins and lipids and DNA inside cells. When the mortality rate was 91.67 %, the Olive Tail Movement (OTM) of the comet experiment reached 15. The results of molecular level tests showed that pyrene inhibited the activity of Cu/Zn-superoxide dismutase (Cu/Zn-SOD) mainly by changing the microenvironment and secondary structure of amino acid Tyr 108. The weakened function of direct antioxidant enzymes may be the root cause of the excessive increase of reactive oxygen species (ROS) in cells. The systematic approach used in this study enriches the network of toxic pathways in toxicological studies, and basic data on the biological toxicity of pyrene can provide support for future soil contamination detection.

Computational Study on Temperature Driven Structure-Function Relationship of Polysaccharide Producing Bacterial Glycosyl Transferase Enzyme.

Glycosyltransferase (GTs) is a wide class of enzymes that transfer sugar moiety, playing a key role in the synthesis of bacterial exopolysaccharide (EPS) biopolymer. In recent years, increased demand for bacterial EPSs has been observed in pharmaceutical, food, and other industries. The application of the EPSs largely depends upon their thermal stability, as any industrial application is mainly reliant on slow thermal degradation. Keeping this in context, EPS producing GT enzymes from three different bacterial sources based on growth temperature (mesophile, thermophile, and hyperthermophile) are considered for in silico analysis of the structural–functional relationship. From the present study, it was observed that the structural integrity of GT increases significantly from mesophile to thermophile to hyperthermophile. In contrast, the structural plasticity runs in an opposite direction towards mesophile. This interesting temperature-dependent structural property has directed the GT–UDP-glucose interactions in a way that thermophile has finally demonstrated better binding affinity (−5.57 to −10.70) with an increased number of hydrogen bonds (355) and stabilizing amino acids (Phe, Ala, Glu, Tyr, and Ser). The results from this study may direct utilization of thermophile-origin GT as best for industrial-level bacterial polysaccharide production.

Amino Acid Signature in Urine is Associated With Cardiovascular Risk in Brazilian Children

Childhood obesity is a complex multifactorial disease that contributes to higher cardiometabolic risk. Other important parameter is the pattern of fat distribution, even among normal weight children, those with central fat deposition show higher cardiovascular risk. The waist to height ratio (WHtR) is a useful and practical tool to assess central obesity and cardiovascular risk. Childhood obesity is associated with metabolic abnormalities which are mechanisms underlying cardiovascular diseases. The metabolomics can detect biomarkers for exposure, disease progression and susceptibility contributing to early intervention strategies. In this cross-sectional study it was evaluated the profile of amino acids in urine of children with different cardiovascular risk status according to WHtR. The 110 participants aged from 9 to 10 years were classified according to WHtR into the groups: high cardiovascular risk (n = 48) and normal cardiovascular risk (n = 62). The 24 hours urine samples were collected, and aliquots submitted to LC–MS/MS for evaluation of 47 amino acids using the Amino Acids Analysis Kit (Zivak®, Turkey), values were corrected by creatinine. Biochemical profile, cardiovascular parameters and anthropometric measurements were assessed following standard protocols. The following amino acids were found in higher concentrations in urine of children from high cardiovascular risk group, cystathionine (25 vs 21 nmol/mg of creatinine, p = 0.03), Lys (212 vs 160, p < 0.01) and the aromatic amino acids Tyr (131 vs 90, p < 0.01), Trp (109 vs 95, p =0.02) and Phe (65 vs 46, p = 0.04). Linear regression identified that cystathionine, Lys, Tyr, Trp and Phe presented weak but significant positive correlation with anthropometric measurements. Cystathionine, Trp and Lys negatively correlates with HDL while Phe and Tyr positively correlated with triglycerides. Also, Lys and Tyr were positively associated with higher systolic blood pressure. Findings corroborate to literature and indicate that there is a signature profile of amino acids in urine of children with increased cardiovascular risk associated to central obesity. The augmented Tyr and Lys may be the most significant markers once they were also associated to higher SBP.

Source, distribution and degradation of sedimentary organic matter in the South Yellow Sea and East China Sea

Sedimentary organic matter (SOM) plays an important role in marine carbon and nitrogen cycling, but the sources, degradation states and fates of SOM are not well understood. In the present study, we determined the total organic carbon (TOC), total nitrogen (TN), stable carbon isotope (δ13C), and total hydrolysable amino acids (THAA) to elucidate the sources and degradation states of SOM in the South Yellow Sea (SYS) and the East China Sea (ECS). THAA concentrations ranged from 4.90 to 29.13 μmol/g, with a mean of 11.03 ± 5.06 μmol/g. The distribution pattern of THAA was similar to that of TOC (r = 0.782, P < 0.01) and TN (r = 0.865, P < 0.01), with higher THAA concentrations in the coastal areas. Based on the two end-member mixing model, the fraction of terrestrial organic matter (Ft) ranged from 12.11% to 51.34% (average: 30.17 ± 9.61%), with much higher variability at the nearshore stations compared to the offshore stations. The C/N ratios and the δ13C values showed the different distribution trend, and there was a negative correlation between them (r = −0.479, P < 0.05). Based on the C/N ratios and δ13C values, the SOM in the study area was a mixture of marine organic matter (OM) and soil-derived OM. In addition, our study showed that SOM was dominated by diatomaceous OM compared to carbonate-derived OM and that terrestrial inputs and primary production were the dominant factors controlling the distribution of OM in the study area. Carbon and nitrogen-normalized yields of THAA (THAA-C% and THAA-N%) showed that relatively fresh OM tended to occur in the coastal areas off the Shandong Peninsula. However, the generally low degradation index (DI) values revealed that all SOM in the study area had undergone significant degradation. Glycine increased in relative abundance as the SOM was degraded, while aromatic amino acids (Tyr and Phe) and neutral amino acids (Leu, Ile and Val) had consistently decreasing trends following SOM degradation.

Proteolysis and ACE-inhibitory peptide profile of Cheddar cheese: Effect of digestion treatment and different probiotics

Proteolysis degree, ACE-inhibitory (ACE-I) activity, water-soluble peptide profiles of Cheddar cheese with different probiotics were determined during digestion period and were comprehensively compared to evaluate the influence of digestion and the addition of different probiotics. After digestion, further hydrolysis of protein led to the production of more low molecular weight peptides, and ACE-I peptides with higher activity were released. ACE-I activity of Cheddar cheese with Lactobacillus helveticus (B4, 86.06%) was significantly (P < 0.05) higher than other cheese groups. Three ACE-I peptides were uniquely presented in B4 before digestion and more new ACE-I peptides were released after digestion. Meanwhile, cheese with Lactobacillus rhamnosus was more likely to produce anti-digestion ACE-I peptides. Most of ACE-I peptides come from β-casein. Hydrophobic amino acids Val, Phe, Pro, Tyr, Leu, and basic amino acids Arg, Lys at the C-terminal were more responsible for the formation of ACE inhibitory peptides that resist digestion. This research provides the basis to increase the exploitation of the health benefits of Cheddar cheese with probiotic.

Escherichia coli FabG 3-ketoacyl-ACP reductase proteins lacking the assigned catalytic triad residues are active enzymes

The FabG 3-ketoacyl-acyl carrier protein (ACP) reductase of Escherichia coli has long been thought to be a classical member of the short-chain alcohol dehydrogenase/reductase (SDR) family. FabG catalyzes the essential 3-ketoacyl-ACP reduction step in the FAS II fatty acid synthesis pathway. Site-directed mutagenesis studies of several other SDR enzymes has identified three highly conserved amino acid residues, Ser, Tyr, and Lys, as the catalytic triad. Structural analyses of E. coli FabG suggested the triad S138-Y151-K155 to form a catalytically competent active site. To test this hypothesis, we constructed a series of E. coli FabG mutants and tested their 3-ketoacyl-ACP reductase activities both in vivo and in vitro. Our data show that plasmid-borne FabG mutants, including the double and triple mutants, restored growth of E. coli and Salmonella enterica fabG temperature-sensitive mutant strains under nonpermissive conditions. In vitro assays demonstrated that all of the purified FabG mutant proteins maintained fatty acid synthetic ability, although the activities of the single mutant proteins were 20% to 50% lower than that of wildtype FabG. The S138A, Y151F, and K155A residue substitutions were confirmed by tandem mass spectral sequencing of peptides that spanned all three residues. We conclude that FabG is not a classical short-chain alcohol dehydrogenase/reductase, suggesting that an alternative mode of 3-ketoacyl-ACP reduction awaits discovery.

Enzymatic valorization process of yellow cocoon waste for production of antioxidative sericin and fibroin film

AbstractBACKGROUNDCocoon waste, solid waste from the silk industry, is currently utilized as low‐cost spun silk yarn. In this study, the enzymatic valorization process of yellow cocoon waste to produce antioxidative sericin hydrolysate and fibroin film was demonstrated.RESULTSThe enzymatic process involving thermostable alkaline protease from Bacillus halodurans SE5 (protease_SE5) was superior to the conventional high temperature and high pressure and 0.5% Na2CO3 processes. Protease_SE5 produced sericin hydrolysate with high peptide concentration (0.335 mg mL–1) and provided degummed fibroin with a complete structure. Sericin hydrolysate from protease_SE5‐assisted hydrolysis showed remarkable radical scavenging activities on ABTS, DPPH and FRAP assays with 602, 3.90 and 24.8 μmol Trolox equivalents (TE) g−1 protein, respectively. After ultrafiltration and size‐exclusion chromatography, two active fractions (F1 and F2) were obtained from sericin hydrolysate with ABTS radical scavenging activity of 2120 and 3289 μmol TE g−1 protein, respectively. Identification of bioactive peptides by de novo sequencing was conducted, and seven candidate peptides were identified with high content of key antioxidative amino acids (His, Phe, Trp, Tyr and Arg) in the sequences. Moreover, bioactivities of several of the peptides were predicted by bioinformatics databases. Besides, the mechanical properties of enzyme‐derived fibroin film were also improved, with tensile strength and elongation at break of 62.1 MPa and 3.6% in the dry state, and 8.5 MPa and 140% in the wet state.CONCLUSIONThis enzymatic process could be an effective way for valorizing cocoon waste. The value‐added products from agricultural waste have promising applications in food, pharmaceutical and biomedical materials. © 2020 Society of Chemical Industry (SCI)