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I Adamska, K Marhelava, D Walkiewicz, U Kedzierska, M Markowska, P M Majewski
Our recent research on the pineal gland of young chickens confirmed that three genes encoding enzymes involved in pineal melatonin biosynthesis, tryptophan hydroxylase 1 (Tph1), arylalkylamine-N-acetyltransferase (Aanat) and acetylserotonin O-methyltransferase (Asmt), are transcribed rhythmically under light:dark (L:D) 12:12 conditions in vivo. Additionally, in the pineal gland of maturing chickens, the dopa decarboxylase (Ddc) gene is transcribed rhythmically at a specific stage of the developmental process...
August 2016: Journal of Physiology and Pharmacology: An Official Journal of the Polish Physiological Society
Bethany G Caulkins, Robert P Young, Ryan A Kudla, Chen Yang, Thomas J Bittbauer, Baback Bastin, Eduardo Hilario, Li Fan, Michael J Marsella, Michael F Dunn, Leonard J Mueller
Carbanionic intermediates play a central role in the catalytic transformations of amino acids performed by pyridoxal-5'-phosphate (PLP)-dependent enzymes. Here, we make use of NMR crystallography - the synergistic combination of solid-state nuclear magnetic resonance, X-ray crystallography, and computational chemistry - to interrogate a carbanionic/quinonoid intermediate analogue in the β-subunit active site of the PLP-requiring enzyme tryptophan synthase. The solid-state NMR chemical shifts of the PLP pyridine ring nitrogen and additional sites, coupled with first principles computational models, allow a detailed model of protonation states for ionizable groups on the cofactor, substrates, and nearby catalytic residues to be established...
October 25, 2016: Journal of the American Chemical Society
Paula Honório de Melo Martimiano, André de Sa Braga Oliveira, Véronique Ferchaud-Roucher, Mikaël Croyal, Audrey Aguesse, Isabelle Grit, Khadija Ouguerram, Sandra Lopes de Souza, Bertrand Kaeffer, Francisco Bolaños-Jiménez
Early malnutrition is a risk factor for depression and schizophrenia. Since the offspring of malnourished dams exhibit increased brain levels of serotonin (5-HT), a tryptophan-derived neurotransmitter involved in the pathophysiology of these mental disorders, it is believed that the deleterious effects of early malnutrition on brain function are due in large part to altered serotoninergic neurotransmission resulting from impaired tryptophan (Trp) metabolism. However, tryptophan is also metabolized through the kynurenine (KYN) pathway yielding several neuroactive compounds including kynurenic (KA), Qinolinic (QA) and Xanthurenic (XA) acids...
October 25, 2016: Journal of Neurochemistry
Miaomiao Bai, Hongnan Liu, Kang Xu, Abimbola Oladele Oso, Xin Wu, Gang Liu, Myrlene Carine B Tossou, Naif Abdullah Al-Dhabi, Veeramuthu Duraipandiyan, Qianyun Xi, Yinlong Yin
Tryptophan, a nutritionally essential amino acid, is active in the regulation of immune responses in animals. The products of tryptophan metabolism, such as indoleamine 2,3-dioxygenase, kynurenine, quinolinic acid, and melatonin, may improve immunity in an organism and induce anti-inflammatory responses. The immune tolerance processes mediated by tryptophan metabolites are not well understood. Recent studies have reported that the enzymes that break down tryptophan through the kynurenine metabolic pathway are found in numerous cell types, including immunocytes...
October 24, 2016: Amino Acids
Chimoné S Dalton, Karen van de Rakt, Åsa Fahlman, Kathreen Ruckstuhl, Peter Neuhaus, Richard Popko, Susan Kutz, Frank van der Meer
Herpesviruses (HVs) have a wide range of hosts in the animal kingdom. The result of infection with HVs can vary from asymptomatic to fatal diseases depending on subtype, strain, and host. To date, little is known about HVs naturally circulating in wildlife species and the impact of these viruses on other species. In our study, we used genetic and comparative approaches to increase our understanding of circulating HVs in Canadian wildlife. Using nested polymerase chain reaction targeting a conserved region of the HV DNA polymerase gene, we analyzed material derived from wildlife of western and northern Canada collected between February 2009 and Sept 2014...
October 24, 2016: Archives of Virology
Cuixia Gao, Bingxian Yang, Dandan Zhang, Meng Chen, Jingkui Tian
BACKGROUND: Indole alkaloids, which characteristically contain an indole nucleus, have pharmaceutical potential in a diverse range of applications. UV-B can elicit the accumulation of indole alkaloids. The indole alkaloid (6-hydroxyl-1H-indol-3-yl) carboxylic acid methyl ester with cytotoxic activity was found to accumulate in Clematis terniflora DC. leaves after exposure to high level of UV-B irradiation and the dark. However, a more in-depth analysis of the process behind this response has not yet been performed...
October 24, 2016: BMC Plant Biology
Lihui Men, Zifeng Pi, Yuan Zhou, Mengying Wei, Yuanyuan Liu, Fengrui Song, Zhongying Liu
Obesity has become a global epidemic and public health challenge which associates with serious health issues including diabetes, cardiovascular disease, stroke, arthritis, and some types of cancer. To better understand obesity and obesity-related dysfunction, a high-fat diet (HFD) induced obese model was developed on Sprague-Dawley rats. Metabolomics based on ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) was untilized to identify and analyze obesity related metabolites in rat urine samples...
October 14, 2016: Journal of Pharmaceutical and Biomedical Analysis
Zahra Aghili, Saba Taheri, Hojjat Alizadeh Zeinabad, Leila Pishkar, Ali Akbar Saboury, Arash Rahimi, Mojtaba Falahati
Herein, the interaction of hen egg white lysozyme (HEWL) with iron nanoparticle (Fe NP) was investigated by spectroscopic and docking studies. The zeta potential analysis revealed that addition of Fe NP (6.45±1.03 mV) to HEWL (8.57±0.54 mV) can cause to greater charge distribution of nanoparticle-protein system (17.33±1.84 mV). In addition, dynamic light scattering (DLS) study revealed that addition of Fe NP (92.95±6.11 nm) to HEWL (2.68±0.37 nm) increases suspension potential of protein/nanoparticle system (51...
2016: PloS One
Monika B Dolinska, Nicole Kus, Katie Farney, Paul T Wingfield, Brian P Brooks, Yuri V Sergeev
: Oculocutaneous albinism Type 1 (OCA1) is an autosomal recessive disorder caused by mutations in the tyrosinase gene. Two subtypes of OCA1 have been described: severe OCA1A with complete absence of tyrosinase activity and less severe OCA1B with residual tyrosinase activity. Here, we characterize the recombinant human tyrosinase intra-melanosomal domain and mutant variants, which mimic genetic changes in both subtypes of OCA1 patients. Proteins were prepared using site-directed mutagenesis, expressed in insect larvae, purified by chromatography, and characterized by enzymatic activities- tryptophan fluorescence, and Gibbs free energy changes...
October 24, 2016: Pigment Cell & Melanoma Research
Shun Wang, Zhe Dong, Shen Li, Haotian Yin, Zhifu Zhao, Dongmei Gao, Guimin Ren, Xuexiang Bao
Tryptophan hydroxylase (TPH) was stained in the central nervous system of the Neanthes japonica (Polychaeta, Annelida), using sheep anti-tryptophan hydroxylase antibody by the Streptavidin-Peroxidase immunohistochemical method and Colophony-Paraffin embedded section technique. The immunohistochemistry results revealed that the TPH is distributed in the brain and ventral nerve cord, which is consistent with that of serotonin (5-hydroxytryptamine, 5-HT) that labeled by anti-serotonin antibody. Using the rapid amplification of cDNA ends (RACE) technique, TPH cDNA cloned from Neanthes japonica's central nervous system was 1778bp, which encodes predicted protein of 463 amino acid residues...
October 24, 2016: Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
Elisete P Rodrigues, Cleiton de Paula Soares, Patrícia G Galvão, Eddie L Imada, Jean L Simões-Araújo, Luc F M Rouws, André L M de Oliveira, Márcia S Vidal, José I Baldani
Gluconacetobacter diazotrophicus is a beneficial nitrogen-fixing endophyte found in association with sugarcane plants and other important crops. Beneficial effects of G. diazotrophicus on sugarcane growth and productivity have been attributed to biological nitrogen fixation process and production of phytohormones especially indole-3-acetic acid (IAA); however, information about the biosynthesis and function of IAA in G. diazotrophicus is still scarce. Therefore, the aim of this work was to identify genes and pathways involved in IAA biosynthesis in this bacterium...
2016: Frontiers in Microbiology
Matteo Mori, Miguel Ponce-de-León, Juli Peretó, Francisco Montero
Bacterial communities may display metabolic complementation, in which different members of the association partially contribute to the same biosynthetic pathway. In this way, the end product of the pathway is synthesized by the community as a whole. However, the emergence and the benefits of such complementation are poorly understood. Herein, we present a simple model to analyze the metabolic interactions among bacteria, including the host in the case of endosymbiotic bacteria. The model considers two cell populations, with both cell types encoding for the same linear biosynthetic pathway...
2016: Frontiers in Microbiology
Jean-Pierre Routy, Bertrand Routy, Gina M Graziani, Vikram Mehraj
The term "immune privilege" was originally coined to describe the suppression of inflammatory responses within organs protected by anatomic barriers, ie, the eyes, brain, placenta, and testes. However, cellular and metabolic processes, which orchestrate immune responses, also control inflammation within these sites. Our current understanding of tolerogenic mechanisms has extended the definition of immune privilege to include hair follicles, the colon, and cancer. By catabolizing tryptophan, cells expressing the enzyme indoleamine-2,3-dioxygenase produce kynurenine metabolites, which orchestrate local and systemic responses to control inflammation, thus maintaining immune privilege...
2016: International Journal of Tryptophan Research: IJTR
Ana Sofia Pina, Sara Carvalho, Ana Margarida G C Dias, Márcia Guilherme, Alice S Pereira, Luciana T Caraça, Ana Sofia Coroadinha, Christopher R Lowe, A Cecília A Roque
A common strategy for the production and purification of recombinant proteins is to fuse a tag to the protein terminal residues and employ a "tag-specific" ligand for fusion protein capture and purification. In this work, we explored the effect of two tryptophan-based tags, NWNWNW and WFWFWF, on the expression and purification of Green Fluorescence Protein (GFP) used as a model fusion protein. The titers obtained with the expression of these fusion proteins in soluble form were 0.11mgml(-1) and 0.48mgml(-1) for WFWFWF and NWNWNW, respectively...
October 19, 2016: Journal of Chromatography. A
Auksė Zinkevičienė, Denis Kainov, Irutė Girkontaitė, Eglė Lastauskienė, Violeta Kvedarienė, Yu Fu, Simon Anders, Vidya Velagapudi
BACKGROUND: Allergic contact dermatitis (ACD) is an inflammatory skin disease caused by repeated skin exposure to contact allergens. The severity and duration of this disease are associated with many different factors. Some of these factors may represent markers for monitoring disease activity and the individual response to an intervention. METHODS: We used a targeted metabolomics approach to find such factors in the serum of individuals with ACD. Metabolomics profiles were examined and compared in the acute phase of the disease and also in the absence of disease activity...
October 22, 2016: International Archives of Allergy and Immunology
Shan Qian, Tao He, Wei Wang, Yanying He, Man Zhang, Lingling Yang, Guobo Li, Zhouyu Wang
Indoleamine 2,3-dioxygenase 1 (IDO1)-mediated kynurenine pathway of tryptophan degradation is identified as an important immune effector pathway in the tumor cells to escape a potentially effective immune response. IDO1 is an attractive target for anticancer therapy and the discovery of IDO1 inhibitors has been intensely ongoing in both academic research laboratories and pharmaceutical organizations. Our study discovered that 1H-indazole was a novel key pharmacophore with potent IDO1 inhibitory activity. A series of new 1H-indazole derivatives were synthesized and determined the enzyme inhibitory activities, and the compound 2g exhibited the highest activity with an IC50 value of 5...
October 6, 2016: Bioorganic & Medicinal Chemistry
Xiaoxue Tong, Tania Triscari Barberi, Catherine H Botting, Sunil V Sharma, Mark J H Simmons, Tim W Overton, Rebecca J M Goss
BACKGROUND: Engineering of single-species biofilms for enzymatic generation of fine chemicals is attractive. We have recently demonstrated the utility of an engineered Escherichia coli biofilm as a platform for synthesis of 5-halotryptophan. E. coli PHL644, expressing a recombinant tryptophan synthase, was employed to generate a biofilm. Its rapid deposition, and instigation of biofilm formation, was enforced by employing a spin-down method. The biofilm presents a large three-dimensional surface area, excellent for biocatalysis...
October 21, 2016: Microbial Cell Factories
Anirban Basu, Gopinatha Suresh Kumar
Interaction of proflavine with hemoglobin (Hgb) was studied employing spectroscopy, calorimetry, and atomic force microscopy. The equilibrium constant was found to be of the order 10(4)M(-1). The quenching of Hgb fluorescence by proflavine was due to the complex formation. Calculation of the molecular distance (r) between the donor (β-Trp37 of Hgb) and acceptor (proflavine) suggested that energy can be efficiently transferred from the β-Trp37 residue at the α1β2 interface of the protein to the dye. Proflavine induced significant secondary structural changes in Hgb...
October 12, 2016: Journal of Photochemistry and Photobiology. B, Biology
Shelby Calkins, M B Couger, Colin Jackson, Jordan Zandler, Garett C Hudgins, Radwa A Hanafy, Connie Budd, Donald P French, Wouter D Hoff, Noha Youssef
Staphylococcus hominis is a predominant member of the human skin microbiome. We here report on the genomic analysis of Staphylococcus hominis strain Hudgins that was isolated from the wrist area of human skin. The partial genome assembly of S. hominis Hudgins consists of 2,211,863 bp of DNA with 2174 protein-coding genes and 90 RNA genes. Based on the genomic analysis of KEGG pathways, the organism is expected to be a versatile heterotroph potentially capable of hydrolyzing the sugars glucose, fructose, mannose, and the amino acids alanine, aspartate, glutamate, glycine, threonine, cysteine, methionine, valine, isoleucine, leucine, lysine, arginine, phenylalanine, tyrosine, and tryptophan for energy production through aerobic respiration, with occasional lactate and acetate fermentation...
December 2016: Genomics Data
Sharon K Michelhaugh, Otto Muzik, Anthony R Guastella, Neil V Klinger, Lisa A Polin, Hancheng Cai, Yanchun Xin, Thomas J Mangner, Shaohui Zhang, Csaba Juhasz, Sandeep Mittal
: Abnormal tryptophan metabolism via the kynurenine pathway (KP) is involved in the pathophysiology of a variety of human diseases including cancers. α-[(11)C]-methyl-L-tryptophan ((11)C-AMT) positron emission tomography (PET) imaging demonstrated increased tryptophan uptake and trapping in epileptic foci and brain tumors, but the short half-life of (11)C limits its widespread clinical application. Recent in vitro studies suggested that the novel radiotracer 1-(2-[(18)F]fluoroethyl)-L-tryptophan ((18)F-FETrp) may be useful to assess tryptophan metabolism via the KP...
October 20, 2016: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
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