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1.
Int J Mol Sci ; 25(7)2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38612864

ABSTRACT

Flavonoids exhibit various bioactivities including anti-oxidant, anti-tumor, anti-inflammatory, and anti-viral properties. Methylated flavonoids are particularly significant due to their enhanced oral bioavailability, improved intestinal absorption, and greater stability. The heterologous production of plant flavonoids in bacterial factories involves the need for enough biosynthetic precursors to allow for high production levels. These biosynthetic precursors are malonyl-CoA and l-tyrosine. In this work, to enhance flavonoid biosynthesis in Streptomyces albidoflavus, we conducted a transcriptomics study for the identification of candidate genes involved in l-tyrosine catabolism. The hypothesis was that the bacterial metabolic machinery would detect an excess of this amino acid if supplemented with the conventional culture medium and would activate the genes involved in its catabolism towards energy production. Then, by inactivating those overexpressed genes (under an excess of l-tyrosine), it would be possible to increase the intracellular pools of this precursor amino acid and eventually the final flavonoid titers in this bacterial factory. The RNAseq data analysis in the S. albidoflavus wild-type strain highlighted the hppD gene encoding 4-hydroxyphenylpyruvate dioxygenase as a promising target for knock-out, exhibiting a 23.2-fold change (FC) in expression upon l-tyrosine supplementation in comparison to control cultivation conditions. The subsequent knock-out of the hppD gene in S. albidoflavus resulted in a 1.66-fold increase in the naringenin titer, indicating enhanced flavonoid biosynthesis. Leveraging the improved strain of S. albidoflavus, we successfully synthesized the methylated flavanones hesperetin, homoeriodictyol, and homohesperetin, achieving titers of 2.52 mg/L, 1.34 mg/L, and 0.43 mg/L, respectively. In addition, the dimethoxy flavanone homohesperetin was produced as a byproduct of the endogenous metabolism of S. albidoflavus. To our knowledge, this is the first time that hppD deletion was utilized as a strategy to augment the biosynthesis of flavonoids. Furthermore, this is the first report where hesperetin and homoeriodictyol have been synthesized from l-tyrosine as a precursor. Therefore, transcriptomics is, in this case, a successful approach for the identification of catabolism reactions affecting key precursors during flavonoid biosynthesis, allowing the generation of enhanced production strains.


Subject(s)
Craniofacial Abnormalities , Flavones , Flavonoids , Gene Expression Profiling , Hesperidin , Streptomyces , Amino Acids , Tyrosine
2.
Environ Res ; 252(Pt 1): 118826, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38579999

ABSTRACT

Nitration of allergenic proteins caused by atmospheric pollutants O3 and NO2 may enhance their allergenic potential. In the study, the influence of nitration was investigated on the allergenicity of Der p 2, which is a main allergen from house dust mites and plays an important role in allergenic rhinitis and asthma. The results reveal that nitrated Der p 2 enhanced the IgE-binding capacity, upregulated the mRNA expression and release of IL-6 and IL-8 from bronchial epithelial cells, and induced higher levels of specific-IgE, TH2 cytokines and white blood cells in mice. Besides, nitrated Der p 2 caused more severe oxidative stress and allergenic symptoms in mice. It is concluded that nitration enhanced the allergenicity of Der p 2 through not only directly inducing higher amount of specific-IgE and stronger responses of TH2 cytokines, but also indirectly aggravating allergic symptoms by oxidative stress and adjuvant-like activation airway epithelial cells. The study suggests that the contribution of nitration to the promotion in allergenicity should not be ignored when precisely assessing the risk of house dust mite allergens in real environment.


Subject(s)
Antigens, Dermatophagoides , Arthropod Proteins , Animals , Antigens, Dermatophagoides/immunology , Arthropod Proteins/immunology , Arthropod Proteins/chemistry , Mice , Tyrosine , Cysteine Endopeptidases/immunology , Mice, Inbred BALB C , Humans , Immunoglobulin E/immunology , Allergens/immunology , Female , Cytokines/immunology , Cytokines/metabolism , Oxidative Stress
3.
ACS Infect Dis ; 10(5): 1552-1560, 2024 05 10.
Article in English | MEDLINE | ID: mdl-38623820

ABSTRACT

Tyrosine cross-linking has recently been used to produce nanoclusters (NCs) from peptides to enhance their immunogenicity. In this study, NCs were generated using the ectodomain of the ion channel Matrix 2 (M2e) protein, a conserved influenza surface antigen. The NCs were administered via intranasal (IN) or intramuscular (IM) routes in a mouse model in a prime-boost regimen in the presence of the adjuvant CpG. After boost, a significant increase in anti-M2e IgG and its subtypes was observed in the serum and lungs of mice vaccinated through the IM and IN routes; however, significant enhancement in anti-M2e IgA in lungs was observed only in the IN group. Analysis of cytokine concentrations in stimulated splenocyte cultures indicated a Th1/Th17-biased response. Mice were challenged with a lethal dose of A/California/07/2009 (H1N1pdm), A/Puerto Rico/08/1934 (H1N1), or A/Hong Kong/08/1968 (H3N2) strains. Mice that received M2e NCs + CpG were significantly protected against these strains and showed decreased lung viral titers compared with the naive mice and M2e NC-alone groups. The IN-vaccinated group showed superior protection against the H3N2 strain as compared to the IM group. This research extends our earlier efforts involving the tyrosine-based cross-linking method and highlights the potential of this technology in enhancing the immunogenicity of short peptide immunogens.


Subject(s)
Antibodies, Viral , Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Orthomyxoviridae Infections , Tyrosine , Animals , Influenza Vaccines/immunology , Influenza Vaccines/administration & dosage , Mice , Orthomyxoviridae Infections/prevention & control , Orthomyxoviridae Infections/immunology , Tyrosine/chemistry , Tyrosine/pharmacology , Influenza A Virus, H1N1 Subtype/immunology , Female , Antibodies, Viral/blood , Antibodies, Viral/immunology , Viral Matrix Proteins/immunology , Viral Matrix Proteins/genetics , Mice, Inbred BALB C , Influenza A Virus, H3N2 Subtype/immunology , Adjuvants, Immunologic/pharmacology , Adjuvants, Immunologic/administration & dosage , Lung/virology , Lung/immunology , Administration, Intranasal , Injections, Intramuscular , Cytokines , Cross Protection , Viroporin Proteins
4.
BMC Plant Biol ; 24(1): 276, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605285

ABSTRACT

BACKGROUND: Stephania kwangsiensis Lo (Menispermaceae) is a well-known Chinese herbal medicine, and its bulbous stems are used medicinally. The storage stem of S. kwangsiensis originated from the hypocotyls. To date, there are no reports on the growth and development of S. kwangsiensis storage stems. RESULTS: The bulbous stem of S. kwangsiensis, the starch diameter was larger at the stable expanding stage (S3T) than at the unexpanded stage (S1T) or the rapidly expanding stage (S2T) at the three different time points. We used ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and Illumina sequencing to identify key genes involved in bulbous stem development. A large number of differentially accumulated metabolites (DAMs) and differentially expressed genes (DEGs) were identified. Based on the differential expression profiles of the metabolites, alkaloids, lipids, and phenolic acids were the top three differentially expressed classes. Compared with S2T, significant changes in plant signal transduction and isoquinoline alkaloid biosynthesis pathways occurred at both the transcriptional and metabolic levels in S1T. In S2T compared with S3T, several metabolites involved in tyrosine metabolism were decreased. Temporal analysis of S1T to S3T indicated the downregulation of phenylpropanoid biosynthesis, including lignin biosynthesis. The annotation of key pathways showed an up-down trend for genes and metabolites involved in isoquinoline alkaloid biosynthesis, whereas phenylpropanoid biosynthesis was not completely consistent. CONCLUSIONS: Downregulation of the phenylpropanoid biosynthesis pathway may be the result of carbon flow into alkaloid synthesis and storage of lipids and starch during the development of S. kwangsiensis bulbous stems. A decrease in the number of metabolites involved in tyrosine metabolism may also lead to a decrease in the upstream substrates of phenylpropane biosynthesis. Downregulation of lignin synthesis during phenylpropanoid biosynthesis may loosen restrictions on bulbous stem expansion. This study provides the first comprehensive analysis of the metabolome and transcriptome profiles of S. kwangsiensis bulbous stems. These data provide guidance for the cultivation, breeding, and harvesting of S. kwangsiensis.


Subject(s)
Alkaloids , Plants, Medicinal , Stephania , Stephania/chemistry , Stephania/metabolism , Plants, Medicinal/metabolism , Chromatography, Liquid/methods , Lignin/metabolism , Tandem Mass Spectrometry , Plant Breeding , Gene Expression Profiling , Transcriptome , Alkaloids/metabolism , Starch/metabolism , Isoquinolines/metabolism , Tyrosine/metabolism , Lipids , Gene Expression Regulation, Plant
5.
Am J Bot ; 111(4): e16308, 2024 04.
Article in English | MEDLINE | ID: mdl-38581167

ABSTRACT

PREMISE: Better understanding of the relationship between plant specialized metabolism and traditional medicine has the potential to aid in bioprospecting and untangling of cross-cultural use patterns. However, given the limited information available for metabolites in most plant species, understanding medicinal use-metabolite relationships can be difficult. The order Caryophyllales has a unique pattern of lineages of tyrosine- or phenylalanine-dominated specialized metabolism, represented by mutually exclusive anthocyanin and betalain pigments, making Caryophyllales a compelling system to explore the relationship between medicine and metabolites by using pigment as a proxy for dominant metabolism. METHODS: We compiled a list of medicinal species in select tyrosine- or phenylalanine-dominant families of Caryophyllales (Nepenthaceae, Polygonaceae, Simmondsiaceae, Microteaceae, Caryophyllaceae, Amaranthaceae, Limeaceae, Molluginaceae, Portulacaceae, Cactaceae, and Nyctaginaceae) by searching scientific literature until no new uses were recovered. We then tested for phylogenetic clustering of uses using a "hot nodes" approach. To test potential non-metabolite drivers of medicinal use, like how often humans encounter a species (apparency), we repeated the analysis using only North American species across the entire order and performed phylogenetic generalized least squares regression (PGLS) with occurrence data from the Global Biodiversity Information Facility (GBIF). RESULTS: We hypothesized families with tyrosine-enriched metabolism would show clustering of different types of medicinal use compared to phenylalanine-enriched metabolism. Instead, wide-ranging, apparent clades in Polygonaceae and Amaranthaceae are overrepresented across nearly all types of medicinal use. CONCLUSIONS: Our results suggest that apparency is a better predictor of medicinal use than metabolism, although metabolism type may still be a contributing factor.


Subject(s)
Caryophyllales , Plants, Medicinal , Caryophyllales/metabolism , Caryophyllales/genetics , Plants, Medicinal/metabolism , Medicine, Traditional , Phylogeny , Tyrosine/metabolism , Betalains/metabolism , Phenylalanine/metabolism
6.
Theriogenology ; 219: 167-179, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38437767

ABSTRACT

Porcine seminal plasma (SP) is loaded with a heterogeneous population of extracellular vesicles (sEVs) that modulate several reproductive-related processes. This study investigated the effect of two sEV subsets, small (S-sEVs) and large (L-sEVs), on porcine in vitro fertilization (IVF). The sEVs were isolated from nine SP pools (five ejaculates/pool) using a size-exclusion chromatography-based procedure and characterized for quantity (total protein), morphology (cryogenic electron microscopy), size distribution (dynamic light scattering), purity and EV-protein markers (flow cytometry; albumin, CD81, HSP90ß). The characterization confirmed the existence of two subsets of high purity (low albumin content) sEVs that differed in size (S- and L-sEVs). In vitro fertilization was performed with in vitro matured oocytes and frozen-thawed spermatozoa and the IVF medium was supplemented during gamete coincubation (1 h at 38.5 °C, 5 % CO2 in a humidified atmosphere) with three different concentrations of each sEV subset: 0 (control, without sEVs), 0.1, and 0.2 mg/mL. The first experiment showed that sEVs, regardless of subset and concentration, decreased penetration rates and total IVF efficiency (P < 0.0001). In a subsequent experiment, it was shown that sEVs, regardless of subset and concentration, impaired the ability of spermatozoa to bind to the zona pellucida of oocytes (P < 0.0001). The following experiment showed that sEVs, regardless of the subset, bound to frozen-thawed sperm but not to in vitro matured oocytes, indicating that sEVs would affect sperm functionality but not oocyte functionality. The lack of effect on oocytes was confirmed by incubating sEVs with oocytes prior to IVF, achieving sperm-zona pellucida binding results similar to those of control. In the last experiment, conducted under IVF conditions, sperm functionality was analyzed in terms of tyrosine phosphorylation, acrosome integrity and metabolism. The sEVs, regardless of the subset, did not affect sperm tyrosine phosphorylation or acrosome integrity, but did influence sperm metabolism by decreasing sperm ATP production under capacitating conditions. In conclusion, this study demonstrated that the presence of sEVs on IVF medium impairs IVF outcomes, most likely by altering sperm metabolism.


Subject(s)
Semen , Sperm-Ovum Interactions , Male , Swine , Animals , Fertilization in Vitro/veterinary , Fertilization in Vitro/methods , Spermatozoa/metabolism , Oocytes , Zona Pellucida/metabolism , Albumins/metabolism , Tyrosine/metabolism
7.
Nat Commun ; 15(1): 2202, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38485927

ABSTRACT

Viral fusion proteins facilitate cellular infection by fusing viral and cellular membranes, which involves dramatic transitions from their pre- to postfusion conformations. These proteins are among the most protective viral immunogens, but they are metastable which often makes them intractable as subunit vaccine targets. Adapting a natural enzymatic reaction, we harness the structural rigidity that targeted dityrosine crosslinks impart to covalently stabilize fusion proteins in their native conformations. We show that the prefusion conformation of respiratory syncytial virus fusion protein can be stabilized with two engineered dityrosine crosslinks (DT-preF), markedly improving its stability and shelf-life. Furthermore, it has 11X greater potency as compared with the DS-Cav1 stabilized prefusion F protein in immunogenicity studies and overcomes immunosenescence in mice with simply a high-dose formulation on alum.


Subject(s)
Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus Vaccines , Respiratory Syncytial Virus, Human , Tyrosine/analogs & derivatives , Animals , Mice , Antibodies, Neutralizing , Antibodies, Viral , Tyrosine/metabolism , Viral Fusion Proteins , Respiratory Syncytial Virus Infections/prevention & control
8.
Biomacromolecules ; 25(3): 1916-1922, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38315982

ABSTRACT

Selective one-dimensional 13C-13C spin-diffusion solid-state nuclear magnetic resonance (SSNMR) provides evidence for CH/π ring packing interactions between Pro and Tyr residues in 13C-enriched Latrodectus hesperus dragline silk. The secondary structure of Pro-containing motifs in dragline spider silks consistently points to an elastin-like type II ß-turn conformation based on 13C chemical shift analysis. 13C-13C spin diffusion measurements as a function of mixing times allow for the measurement of spatial proximity between the Pro and Tyr rings to be ∼0.5-1 nm, supporting strong Pro-Tyr ring interactions that likely occur through a CH/π mechanism. These results are supported by molecular dynamics (MD) simulations and analysis and reveals new insights into the secondary structure and Pro-Tyr ring stacking interactions for one of nature's toughest biomaterials.


Subject(s)
Black Widow Spider , Spiders , Animals , Silk/chemistry , Tyrosine , Black Widow Spider/chemistry , Molecular Dynamics Simulation , Proline , Magnetic Resonance Spectroscopy
9.
PLoS One ; 19(2): e0296960, 2024.
Article in English | MEDLINE | ID: mdl-38394155

ABSTRACT

Tubulin tyrosine ligase 12 (TTLL12) is a promising target for therapeutic intervention since it has been implicated in tumour progression, the innate immune response to viral infection, ciliogenesis and abnormal cell division. It is the most mysterious of a fourteen-member TTL/TTLL family, since, although it is the topmost conserved in evolution, it does not have predicted enzymatic activities. TTLL12 seems to act as a pseudo-enzyme that modulates various processes indirectly. Given the need to target its functions, we initially set out to identify a property of TTLL12 that could be used to develop a reliable high-throughput screening assay. We discovered that TTLL12 suppresses the cell toxicity of nitrotyrosine (3-nitrotyrosine) and its ligation to the C-terminus of detyrosinated α-tubulin (abbreviated to ligated-nitrotyrosine). Nitrotyrosine is produced by oxidative stress and is associated with cancer progression. Ligation of nitrotyrosine has been postulated to be a check-point induced by excessive cell stress. We found that the cytotoxicities of nitrotyrosine and tubulin poisons are independent of one another, suggesting that drugs that increase nitrotyrosination could be complementary to current tubulin-directed therapeutics. TTLL12 suppression of nitrotyrosination of α-tubulin was used to develop a robust cell-based ELISA assay that detects increased nitrotyrosination in cells that overexpress TTLL12 We adapted it to a high throughput format and used it to screen a 10,000 molecule World Biological Diversity SETTM collection of low-molecular weight molecules. Two molecules were identified that robustly activate nitrotyrosine ligation at 1 µM concentration. This is the pioneer screen for molecules that modulate nitrotyrosination of α-tubulin. The molecules from the screen will be useful for the study of TTLL12, as well as leads for the development of drugs to treat cancer and other pathologies that involve nitrotyrosination.


Subject(s)
Neoplasms , Tubulin , Tyrosine/analogs & derivatives , Humans , Tyrosine/pharmacology , Cell Division , Microtubules
10.
Int J Food Microbiol ; 415: 110631, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38402671

ABSTRACT

Hanseniaspora vineae exhibits extraordinary positive oenological characteristics contributing to the aroma and texture of wines, especially by its ability to produce great concentrations of benzenoid and phenylpropanoid compounds compared with conventional Saccharomyces yeasts. Consequently, in practice, sequential inoculation of H. vineae and Saccharomyces cerevisiae allows to improve the aromatic quality of wines. In this work, we evaluated the impact on wine aroma produced by increasing the concentration of phenylalanine, the main amino acid precursor of phenylpropanoids and benzenoids. Fermentations were carried out using a Chardonnay grape juice containing 150 mg N/L yeast assimilable nitrogen. Fermentations were performed adding 60 mg/L of phenylalanine without any supplementary addition to the juice. Musts were inoculated sequentially using three different H. vineae strains isolated from Uruguayan vineyards and, after 96 h, S. cerevisiae was inoculated to complete the process. At the end of the fermentation, wine aromas were analysed by both gas chromatography-mass spectrometry and sensory evaluation through a panel of experts. Aromas derived from aromatic amino acids were differentially produced depending on the treatments. Sensory analysis revealed more floral character and greater aromatic complexity when compared with control fermentations without phenylalanine added. Moreover, fermentations performed in synthetic must with pure H. vineae revealed that even tyrosine can be used in absence of phenylalanine, and phenylalanine is not used by this yeast for the synthesis of tyrosine derivatives.


Subject(s)
Hanseniaspora , Wine , Wine/analysis , Fermentation , Saccharomyces cerevisiae/metabolism , Odorants/analysis , Phenylalanine/analysis , Phenylalanine/metabolism , Hanseniaspora/metabolism , Tyrosine/analysis , Tyrosine/metabolism
11.
FEBS J ; 291(13): 2876-2896, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38362811

ABSTRACT

Responsible for synthesizing the complementary strand of the DNA template, DNA polymerase is a crucial enzyme in DNA replication, recombination and repair. A highly conserved tyrosine (Tyr), located at the C-terminus of the O-helix in family A DNA polymerases, plays a critical role in enzyme activity and fidelity. Here, we combined the technology of genetic code extension to incorporate non-canonical amino acids and molecular dynamics (MD) simulations to uncover the mechanisms by which Tyr671 impacts substrate binding and conformation transitions in a DNA polymerase from Thermus aquaticus. Five non-canonical amino acids, namely l-3,4-dihydroxyphenylalanine (l-DOPA), p-aminophenylalanine (pAF), p-acetylphenylalanine (pAcF), p-cyanophenylalanine (pCNF) and p-nitrophenylalanine (pNTF), were individually incorporated at position 671. Strikingly, Y671pAF and Y671DOPA were active, but with lower activity compared to Y671F and wild-type. Y671pAF showed a higher fidelity than the Y671F, despite both possessing lower fidelity than the wild-type. Metadynamics and long-timescale MD simulations were carried out to probe the role of mutations in affecting protein structure, including open conformation, open-to-closed conformation transition, closed conformation, and closed-to-open conformation transition. The MD simulations clearly revealed that the size of the 671 amino acid residue and interactions with substrate or nearby residues were critical for Tyr671 to determine enzyme activity and fidelity.


Subject(s)
Molecular Dynamics Simulation , Taq Polymerase , Tyrosine , Tyrosine/chemistry , Tyrosine/genetics , Tyrosine/metabolism , Taq Polymerase/metabolism , Taq Polymerase/chemistry , Taq Polymerase/genetics , Thermus/enzymology , Thermus/genetics , Amino Acids/chemistry , Amino Acids/metabolism , Amino Acids/genetics , Protein Conformation , Substrate Specificity , Kinetics
12.
Sci Rep ; 14(1): 1093, 2024 01 11.
Article in English | MEDLINE | ID: mdl-38212440

ABSTRACT

One of the main factors considered in assessing the nutritional value of feed is its chemical composition, which can be modified by fertilization. Faced with reducing P resources, alternative sources of this element are being sought. Phosphorus is an essential nutrient in soybean cultivation. The aim of the study was to use an alternative source of phosphorus fertilizer and compare its impact on the chemical composition of soybean seeds with that of a traditional fertilizer (Super FOS DAR). The study investigated a range of factors in animal nutrition as well as the basic content of macro- and microelements. A pot experiment with the Abelina soybean variety was conducted at the Experimental Station of the Wroclaw University of Environmental and Life Sciences. The experiment considered two factors against the control: phosphorus fertilizer placement (band, broadcast) and different phosphorus fertilization (Super FOS DAR, Crystal Green). Use of struvite (Crystal Green)) caused positive changes in selected amino acids content and in the nutritional value of protein in soybean seeds; this can enhance the value of soybean seeds as well as increase certain macroelements and microelements. Phosphorus fertilizer significantly increased the content of lysine, leucine, valine, phenyloalanine and tyrosine. Band fertilization with struvite caused a significant increase in amino acids (lysine, leucine, valine, phenyloalanine and tyrosine) as well as in the nutritional value of protein (as measured by the essential amino acid index, protein efficiency ratio and biological value of the protein). Favorable changes under the influence of the application of struvite were recorded in the content of calcium, as well as phosphorus, iron, and manganese. The value of the struvite in the case of its use as phosphorus fertilizer is promising; however, it needs further study.


Subject(s)
Glycine max , Phosphates , Animals , Struvite/chemistry , Phosphates/chemistry , Fertilizers , Leucine , Lysine , Phosphorus/chemistry , Tyrosine , Valine
13.
J Pharm Biomed Anal ; 241: 115942, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38290190

ABSTRACT

In the present study, a simple, innovative, and economically beneficial method has been proposed for the synthesis of Ag@Ag2O core-shell nanocomposites using Acanthophora muscoides algae extract. The host-guest recognition of targets was performed by modification of the Ag@Ag2O surface using ß-CD. The Ag@Ag2O- ß-CD NCs were used as a colorimetric sensor to determine L-Tryptophan and L-Tyrosine using a partial least square (PLS) approach. A crystalline hybrid structure of Ag core and an Ag2O shell was confirmed by XRD, FTIR, TEM and AFM research. Also, DLS analysis and surface zeta potential spectra illustrated the aggregated nature of nanocomposites in the presence of analytes. The literature review shows that the colorimetric simultaneous determination of L-Tryptophan (L-Try) and L-Tyrosine (L-Tyr) has not been reported. The Ag@Ag2O- ß-CD sensor exhibited outstanding sensing capability in a broad linear range of 2.0 -200 µM for both amino acids and low detection limit of 0.32 and 0.51 µM, for L-Try and L-Tyr, respectively. The good sensitivity and excellent selectivity regarding possible interfering species, originated from the synergistic effect of host-guest recognition in combination with colorimetric sensing. Additionally, determination of analytes in various pharmaceutical, supplement and urine samples, approved the practical applicability of the constructed sensor. The computed results confirmed that colorimetric sensing in conjunction with a PLS technique was appropriate for the precise and accurate simultaneous determination of target amino acids in complex mixtures with RMSEP less than 2.5% and recovery in the range of 103-108% with R.S.D. values less than 3%.


Subject(s)
Nanocomposites , Tryptophan , Tryptophan/analysis , Tyrosine , Colorimetry , Nanocomposites/chemistry , Pharmaceutical Preparations
14.
Langmuir ; 40(2): 1470-1486, 2024 01 16.
Article in English | MEDLINE | ID: mdl-38174846

ABSTRACT

Peptides are able to self-organize in structural elements including cross-ß structures. Taking advantage of this tendency, in the last decades, peptides have been scrutinized as molecular elements for the development of multivalent supramolecular architectures. In this context, different classes of peptides, also with completely aromatic sequences, were proposed. Our previous studies highlighted that the (FY)3 peptide, which alternates hydrophobic phenylalanine and more hydrophilic tyrosine residues, is able to self-assemble, thanks to the formation of both polar and apolar interfaces. It was observed that the replacement of Phe and Tyr residues with other noncoded aromatic amino acids like 2-naphthylalanine (Nal) and Dopa affects the interactions among peptides with consequences on the supramolecular organization. Herein, we have investigated the self-assembling behavior of two novel (FY)3 analogues with Trp and Dopa residues in place of the Phe and Tyr ones, respectively. Additionally, PEGylation of the N-terminus was analyzed too. The supramolecular organization, morphology, and capability to gel were evaluated using complementary techniques, including fluorescence, Fourier transform infrared spectroscopy, and scanning electron microscopy. Structural periodicities along and perpendicular to the fiber axis were detected by grazing incidence wide-angle X-ray scattering. Finally, molecular dynamics studies provided interesting insights into the atomic structure of the cross-ß that constitutes the basic motif of the assemblies formed by these novel peptide systems.


Subject(s)
Tryptophan , Tyrosine , Tyrosine/chemistry , Tryptophan/chemistry , Dihydroxyphenylalanine , Peptides/chemistry , Amino Acids, Aromatic/chemistry
15.
Brief Funct Genomics ; 23(2): 163-179, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-37248673

ABSTRACT

Post-translational modifications (PTMs) either enhance a protein's activity in various sub-cellular processes, or degrade their activity which leads toward failure of intracellular processes. Tyrosine nitration (NT) modification degrades protein's activity that initiates and propagates various diseases including neurodegenerative, cardiovascular, autoimmune diseases and carcinogenesis. Identification of NT modification supports development of novel therapies and drug discoveries for associated diseases. Identification of NT modification in biochemical labs is expensive, time consuming and error-prone. To supplement this process, several computational approaches have been proposed. However these approaches fail to precisely identify NT modification, due to the extraction of irrelevant, redundant and less discriminative features from protein sequences. This paper presents the NTpred framework that is competent in extracting comprehensive features from raw protein sequences using four different sequence encoders. To reap the benefits of different encoders, it generates four additional feature spaces by fusing different combinations of individual encodings. Furthermore, it eradicates irrelevant and redundant features from eight different feature spaces through a Recursive Feature Elimination process. Selected features of four individual encodings and four feature fusion vectors are used to train eight different Gradient Boosted Tree classifiers. The probability scores from the trained classifiers are utilized to generate a new probabilistic feature space, which is used to train a Logistic Regression classifier. On the BD1 benchmark dataset, the proposed framework outperforms the existing best-performing predictor in 5-fold cross validation and independent test evaluation with combined improvement of 13.7% in MCC and 20.1% in AUC. Similarly, on the BD2 benchmark dataset, the proposed framework outperforms the existing best-performing predictor with combined improvement of 5.3% in MCC and 1.0% in AUC. NTpred is publicly available for further experimentation and predictive use at: https://sds_genetic_analysis.opendfki.de/PredNTS/.


Subject(s)
Computational Biology , Proteins , Proteins/metabolism , Amino Acid Sequence , Machine Learning , Tyrosine
16.
J Nat Med ; 78(2): 285-295, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38082192

ABSTRACT

The natural product Honokiol exhibits robust antitumor activity against a range of cancers, and it has also received approval to undergo phase I clinical trial testing. We confrmed that honokiol can promote the apoptotic death of tumor cells through cell experiments. Then siRNA constructs specific for PIAS3, PIAS3 overexpression plasmid and the mutation of the STAT3 Tyr705 residue were used to confirm the mechanism of Honokiol-induced apoptosis. Finally, we confrmed that honokiol can promote PIAS3 upregulation, in turn suppressing STAT3 Tyr705 phosphorylation through the in vivo and in vitro experiments. Honokiol was ultimately found to reduce tumor cell viability by promoting apoptosis through a mechanism dependent on the ability of Honokiol to promote PIAS3 upregulation and the selective inhibition of p-STAT3 (Tyr705) without affecting p-STAT3 (Ser727) or p-STAT1 (Tyr701) levels. PIAS3 knockdown and overexpression in tumor cells altered STAT3 activation and associated DNA binding activity through the control of Tyr705 phosphorylation via PIAS3-STAT3 complex formation, ultimately shaping Honokiol-induced tumor cell apoptosis. Honokiol was also confirmed to significantly prolong the survival of mice bearing xenograft tumors in a PIAS3-dependent fashion. Together, these findings highlight a novel pathway through which Honokiol can promote PIAS3 upregulation, in turn suppressing STAT3 Tyr705 phosphorylation and promoting the apoptotic death of tumor cells.


Subject(s)
Allyl Compounds , Apoptosis , Biphenyl Compounds , Phenols , Tyrosine , Humans , Animals , Mice , Phosphorylation , Up-Regulation , Cell Line, Tumor , Molecular Chaperones/genetics , Molecular Chaperones/metabolism , Protein Inhibitors of Activated STAT/genetics , Protein Inhibitors of Activated STAT/metabolism , STAT3 Transcription Factor/genetics , STAT3 Transcription Factor/metabolism
17.
Vet Res Commun ; 48(2): 1189-1193, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37889425

ABSTRACT

We aimed to investigate the impact of processing boar spermatozoa with phosphate-buffered saline (PBS) at 4 ˚C on acrosomal integrity and increase in 32 kDa tyrosine-phosphorylated protein (p32). Following cooled PBS washing, we observed a significant increase in p32 levels and in the proportion of dead spermatozoa with compromised acrosomal integrity compared to sperm washing using PBS at room temperature. Interestingly, this increase in p32 was effectively inhibited when cooled PBS was supplemented with 1 mM AEBSF, a serine protease inhibitor. Our findings suggest that the increase of p32 in response to cooled PBS washing in boar spermatozoa is associated with enhanced protease activity in dead spermatozoa.


Subject(s)
Phosphates , Spermatozoa , Animals , Male , Phosphates/metabolism , Phosphates/pharmacology , Semen , Spermatozoa/physiology , Swine , Tyrosine/metabolism
18.
J Nucl Med ; 65(1): 16-21, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-37884332

ABSTRACT

Contrast-enhanced MRI is the method of choice for brain tumor diagnostics, despite its low specificity for tumor tissue. This study compared the contribution of MR spectroscopic imaging (MRSI) and amino acid PET to improve the detection of tumor tissue. Methods: In 30 untreated patients with suspected glioma, O-(2-[18F]fluoroethyl)-l-tyrosine (18F-FET) PET; 3-T MRSI with a short echo time; and fluid-attenuated inversion recovery, T2-weighted, and contrast-enhanced T1-weighted MRI were performed for stereotactic biopsy planning. Serial samples were taken along the needle trajectory, and their masks were projected to the preoperative imaging data. Each sample was individually evaluated neuropathologically. 18F-FET uptake and the MRSI signals choline (Cho), N-acetyl-aspartate (NAA), creatine, myoinositol, and derived ratios were evaluated for each sample and classified using logistic regression. The diagnostic accuracy was evaluated by receiver operating characteristic analysis. Results: On the basis of the neuropathologic evaluation of tissue from 88 stereotactic biopsies, supplemented with 18F-FET PET and MRSI metrics from 20 areas on the healthy-appearing contralateral hemisphere to balance the glioma/nonglioma groups, 18F-FET PET identified glioma with the highest accuracy (area under the receiver operating characteristic curve, 0.89; 95% CI, 0.81-0.93; threshold, 1.4 × background uptake). Among the MR spectroscopic metabolites, Cho/NAA normalized to normal brain tissue showed the highest diagnostic accuracy (area under the receiver operating characteristic curve, 0.81; 95% CI, 0.71-0.88; threshold, 2.2). The combination of 18F-FET PET and normalized Cho/NAA did not improve the diagnostic performance. Conclusion: MRI-based delineation of gliomas should preferably be supplemented by 18F-FET PET.


Subject(s)
Brain Neoplasms , Glioma , Humans , Magnetic Resonance Imaging/methods , Glioma/diagnostic imaging , Glioma/metabolism , Magnetic Resonance Spectroscopy , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Positron-Emission Tomography/methods , Tyrosine , Biopsy
19.
Biotechnol Lett ; 46(1): 19-28, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37987932

ABSTRACT

OBJECTIVE: Assembly and construction of resveratrol production pathway in Saccharomyces cerevisiae for denovo production of resveratrol using seaweed extract as fermentation medium. RESULTS: Genes involved in the production of resveratrol from tyrosine pathway, tyrosine ammonia lyase (FTAL) gene from Flavobacterium johnsoniae (FjTAL), the 4-coumarate:CoA ligase gene from Arabidopsis thaliana (4CL1) and the stilbene synthase gene from Vitis vinifera (VvSTS) were introduced into low copy, high copy and integrative vector and transformed into S. cerevisiae W303-1a. The resulting strains W303-1a/pARS-res5, W303-1a/2µ-res1 and W303-1a/IntUra-res9 produced a level of 2.39 ± 0.01, 3.33 ± 0.03 and 8.34 ± 0.03 mg resveratrol l-1 respectively. CRISPR mediated integration at the δ locus resulted in 17.13 ± 1.1 mg resveratrol l-1. Gracilaria corticata extract was tested as a substrate for the growth of transformant to produce resveratrol. The strain produced a comparable level, 13.6 ± 0.54 mg resveratrol l-1 when grown in seaweed extract medium. CONCLUSIONS: The strain W303-1a/IntδC-res1 utilized Gracillaria hydrolysate and produced 13.6 ± 0.54 mg resveratrol l-1 and further investigations are being carried out focusing on pathway engineering and optimization of process parameters to enhance resveratrol yield.


Subject(s)
Arabidopsis , Gracilaria , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Resveratrol/metabolism , Gracilaria/genetics , Gracilaria/metabolism , Arabidopsis/genetics , Tyrosine/metabolism , Plant Extracts
20.
J Ethnopharmacol ; 319(Pt 3): 117359, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-37924999

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Woohwangchungsimwon (WCW) is a traditional medicine used in East Asian countries to treat central nervous system disorders. Reported pharmacological properties include antioxidant effects, enhanced learning and memory, and protection against ischemic neuronal cell death, supporting its use in treating neurodegenerative diseases like Alzheimer's disease (AD). AIM OF THE STUDY: The study aims to assess the effects of co-treatment with WCW and donepezil on cognitive functions and serum metabolic profiles in a scopolamine-induced AD model. MATERIALS AND METHODS: Cell viability and reactive oxygen species (ROS) levels were measured in amyloid ß-peptide25-35 (Aß25-35)-induced SH-SY5Y cells. An AD model was established in ICR mice by intraperitoneal scopolamine administration. Animals underwent the step-through passive avoidance test (PAT) and Morris water maze (MWM) test. Hippocampal tissues were collected to examine specific protein expression. Serum metabolic profiles were analyzed using nuclear magnetic resonance (NMR) spectroscopy. RESULTS: Co-treatment with WCW and donepezil increased cell viability and reduced ROS production in Aß25-35-induced SH-SY5Y cells compared to that with donepezil treatment alone. Co-treatment improved cognitive functions and was comparable to donepezil treatment alone in the PAT and MWM tests. Pathways related to tyrosine, phenylalanine, and tryptophan biosynthesis, phenylalanine metabolism, and cysteine and methionine metabolism were altered by co-treatment. Levels of tyrosine and methionine, major serum metabolites in these pathways, were significantly reduced after co-treatment. CONCLUSIONS: Co-treatment with WCW and donepezil shows promise as a therapeutic strategy for AD and is comparable to donepezil alone in improving cognitive function. Reduced tyrosine and methionine levels after co-treatment may enhance cognitive function by mitigating hypertyrosinemia and hyperhomocysteinemia, known risk factors for AD. The serum metabolic profiles obtained in this study can serve as a foundation for developing other bioactive compounds using a scopolamine-induced mouse model.


Subject(s)
Alzheimer Disease , Neuroblastoma , Humans , Mice , Animals , Mice, Inbred ICR , Alzheimer Disease/chemically induced , Alzheimer Disease/drug therapy , Donepezil , Amyloid beta-Peptides , Reactive Oxygen Species , Cognition , Metabolome , Methionine , Phenylalanine , Tyrosine , Scopolamine Derivatives
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