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Manish Kumar, Amandeep Brar, V Vivekanand, Nidhi Pareek
An extracellular acidic and thermostable chitinase (HgChi) from thermophilic Humicola grisea was purified and characterized. Enhancement in chitinase production (Qp  = 2.9662 Ul-1  h-1 ) was achieved through derivation of optimum fermentation conditions via central composite design. H. grisea observed to produce various isoforms of chitinase, among which the major expressed form has molecular mass of about 50 kDa. Purified chitinases exhibited optimal activity at pH 3.0 and 70 °C. Chitinase showed notable stability at increasing temperatures...
May 18, 2018: International Journal of Biological Macromolecules
Di Wang, Anjie Li, Hongyu Han, Tian Liu, Qing Yang
Bioconversion of chitin-containing waste to N-acetyl-d-glucosamine (GlcNAc) is of economic interest. Highly efficient chitinases are thus desirable. Bacillus subtilis is a well-known microorganism for industrial protein production and biocontrol, however its chitinolytic enzyme has not been studied in detail. In this study, BsChi from B. subtilis was recombinantly expressed in Escherichia coli and characterized as a potent chitinase for degrading crystalline chitin substrates such as α-chitin, β-chitin and crab shells...
May 18, 2018: International Journal of Biological Macromolecules
R S Wahdan-Alaswad, S M Edgerton, H S Salem, A D Thor
Metformin is the most widely administered anti-diabetic agent worldwide. In patients receiving metformin for metabolic syndrome or diabetes, it reduces the incidence and improves the survival of breast cancer (BC) patients. We have previously shown that metformin is particularly potent against triple negative breast cancer (TNBC), with a reduction of proliferation, oncogenicity and motility, inhibition of pro-oncogenic signaling pathways and induction of apoptosis. These BCs are well recognized to be highly dependent on glucose/glucosamine (metabolized through anaerobic glycolysis) and lipids, which are metabolized for the production of energy and cellular building blocks to sustain a high rate of proliferation...
2018: Journal of Oncology Translational Research
Narek Darabedian, Jinxu Gao, Kelly N Chuh, Christina M Woo, Matthew R Pratt
Metabolic chemical reporters of glycosylation in combination with bioorthogonal reactions have been known for two decades and have been used by many different research labs for the identification and visualization of glycoconjugates. More recently, however, they have begun to see utility for the investigation of cellular metabolism and the tolerance of biosynthetic enzymes and glycosyltransferases to dif-ferent sugars. Here, we take this concept one step further by using the metabolic chemical reporter 6-azido-6-deoxy-glucose (6AzGlc)...
May 17, 2018: Journal of the American Chemical Society
Nicholas DiNubile
Glucosamine and chondroitin sulfate, alone or in combination, are used worldwide by individuals suffering from osteoarthritis pain. They are by prescription in some countries but are available as over-the-counter dietary supplements in other countries, such as the United States. The inconclusive results of the National Institutes of Health-sponsored Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) did little to clarify the efficacy of these agents. However, some newer studies have provided a better perspective on the potential benefits that they can offer...
May 16, 2018: Orthopedics
Toshiki Ishikawa, Lin Fang, Emilie A Rennie, Julien Sechet, Jingwei Yan, Beibei Jing, William Moore, Edgar B Cahoon, Henrik V Scheller, Maki Kawai-Yamada, Jennifer C Mortimer
Glycosylinositol phosphorylceramides (GIPCs), which have a ceramide core linked to a glycan headgroup of varying structure, are the major sphingolipids in the plant plasma membrane. Recently, we identified the major biosynthetic genes for GIPC glycosylation in Arabidopsis thaliana, and demonstrated that the glycan headgroup is essential for plant viability. However, the function of GIPCs and the significance of their structural variation are poorly understood. Here, we characterized the Arabidopsis glycosyltransferase GLUCOSAMINE INOSITOLPHOSPHORYLCERAMIDE TRANSFERASE1 (GINT1) and showed that it is responsible for the glycosylation of a subgroup of GIPCs found in seeds and pollen that contain N-acetylglucosamine (GlcNAc) and glucosamine (GlcN; collectively GlcN(Ac))...
May 14, 2018: Plant Physiology
Ching-Long Chen, Yi-Hao Chen, Chang-Min Liang, Ming-Cheng Tai, Da-Wen Lu, Jiann-Torng Chen
Age-related macular degeneration (AMD) is a vision-threatening age-associated disease. The retinal pigment epithelial (RPE) cells phagocytose and digest photoreceptor outer segment (POS). Incomplete digestion of POS leads to lipofuscin accumulation, which contributes to the pathology of the AMD. Autophagy could help reduce the amount of lipofuscin accumulation. In the present study, we evaluated the effects of glucosamine (GlcN), a natural supplement, on the induction of autophagy and POS-derived lipofuscin-like autofluorescence (LLAF) in ARPE-19 cells in vitro, and investigated the potential molecular pathway involved...
May 9, 2018: International Journal of Molecular Sciences
Zhongyu Sun, Can Li, Lian Li, Lei Nie, Qin Dong, Danyang Li, Lingling Gao, Hengchang Zang
N-acetyl-d-glucosamine (GlcNAc) is a microbial fermentation product, and NIR spectroscopy is an effective process analytical technology (PAT) tool in detecting the key quality attribute: the GlcNAc content. Meanwhile, the design of NIR spectrometers is under the trend of miniaturization, portability and low-cost nowadays. The aim of this study was to explore a portable micro NIR spectrometer with the fermentation process. First, FT-NIR spectrometer and Micro-NIR 1700 spectrometer were compared with simulated fermentation process solutions...
May 2, 2018: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Vanessa Dela Justina, Rinaldo R Dos Passos Junior, Alecsander F Bressan, Rita C Tostes, Fernando S Carneiro, Thaigra S Soares, Gustavo T Volpato, Victor Vitorino Lima, Sebastian San Martin, Fernanda R Giachini
AIMS: Hyperglycemia increases glycosylation with O-linked N‑acetyl‑glucosamine (O-GlcNAc) contributing to placental dysfunction and fetal growth impairment. Our aim was to determine how O-GlcNAc levels are affected by hyperglycemia and the O-GlcNAc distribution in different placental regions. MAIN METHODS: Female Wistar rats were divided into the following groups: severe hyperglycemia (>300 mg/dL; n = 5); mild hyperglycemia (>140 mg/dL, at least than two time points during oral glucose tolerance test; n = 7) or normoglycemia (<120 mg/dL; n = 6)...
May 7, 2018: Life Sciences
Seydou Ba, Abdelhakim Alagui, Mohamed Hajjaji
Shrimp shells and waste of olive stones were used as feedstock for the preparation of chitosan and activated carbon. The adsorption of CrVI and CrIII species in aqueous solution by the materials prepared and their blend were studied by using the well-known kinetic and isotherm models, Fourier transform infrared spectroscopy and scanning electron microscope. It was demonstrated that the rates of adsorption were controlled by diffusion inside particles and throughout the liquid film, and adsorption occurred spontaneously (- 26 < ∆G° < - 15 kJ/mol) in the range of 298-333 K, except for that involving CrIII species and activated carbon...
May 7, 2018: Environmental Science and Pollution Research International
Dong Dai, F David Rollo, Jerry Bryant, E Edmund Kim
Objective. 99m Tc-ethylenedicysteine-glucosamine (99m Tc-EC-G) was developed as a potential alternative to 18 F-FDG for cancer imaging. A Phase 2 study was conducted to compare 18 F-FDG PET/CT and 99m Tc-EC-G SPECT/CT in the detection and staging of patients with non-small cell lung cancer (NSCLC). This study was aimed to demonstrate that 99m Tc-EC-G SPECT/CT was not inferior to 18 F-FDG PET/CT in patients with confirmed NSCLC. Methods. Seventeen patients with biopsy proven NSCLC were imaged with 99m Tc-EC-G and 18 F-FDG to detect and stage their cancers...
2018: Contrast Media & Molecular Imaging
Mohd Syed Ahangar, Christopher M Furze, Collette S Guy, Charlotte Cooper, Kathryn S Maskew, Ben Graham, Alexander D Cameron, Elizabeth Fullam
The Mycobacterium tuberculosis (Mtb) pathogen encodes an N -acetylglucosamine-6-phosphate deacetylase enzyme, NagA (Rv3332), that belongs to the amidohydrolase superfamily. NagA enzymes catalyze the deacetylation of N -acetylglucosamine-6-phosphate (GlcNAc6P) to glucosamine-6-phosphate (GlcN6P). NagA is a potential anti-tubercular drug target because it represents the key enzymatic step in the generation of essential amino-sugar precursors required for Mtb cell wall biosynthesis and also influences recycling of cell wall peptidoglycan fragments...
May 4, 2018: Journal of Biological Chemistry
Yoko Sawada, Atsushi Sugimoto, Tomohiro Osaki, Yoshiharu Okamoto
In a previous study by our group, Ajuga decumbens extract (ADE) was demonstrated to decrease the number of osteoclasts in subchondral bone and to have a synergistic effect with glucosamine in improving cartilaginous injuries in a rabbit model of osteoarthritis. In the present study, a concentrate of the useful fraction of ADE, termed extra ADE (EADE), which includes higher concentrations of the active component 20-hydroxyecdysone, was evaluated for its efficacy to accelerate the healing of experimental cartilage injury...
May 2018: Experimental and Therapeutic Medicine
Toru Ogata, Yuki Ideno, Masami Akai, Atsushi Seichi, Hiroshi Hagino, Tsutomu Iwaya, Toru Doi, Keiko Yamada, Ai-Zhen Chen, Yingzi Li, Kunihiko Hayashi
Osteoarthritis (OA) of the knee is one of the main causes of mobility decline in the elderly. Non-surgical treatments such as administration of supplements to strengthen the joint cartilage matrix have become popular not only for pain relief but also for joint preservation. Glucosamine has been used in many countries based on the increasing evidence of its effectiveness for OA. Although there are many previous studies and systematic reviews, the findings vary and different conclusions have been drawn. We aimed to review recent randomized controlled trials on glucosamine for knee OA to reveal up-to-date findings about this supplement...
April 30, 2018: Clinical Rheumatology
Esmee Oussoren, David van Eerd, Elaine Murphy, Robin Lachmann, Jan C van der Meijden, Lies H Hoefsloot, Rob Verdijk, George J G Ruijter, Mario Maas, Carla E M Hollak, Janneke G Langendonk, Ans T van der Ploeg, Mirjam Langeveld
BACKGROUND: Mucolipidosis type III α/β or γ (MLIII) are rare autosomal recessive diseases, in which reduced activity of the enzyme UDP-N-acetyl glucosamine-1-phosphotransferase (GlcNAc-PTase) leads to intra-lysosomal accumulation of different substrates. Publications on the natural history of MLIII, especially the milder forms, are scarce. This study provides a detailed description of the disease characteristics and its natural course in adult patients with MLIII. METHODS: In this retrospective chart study, the clinical, biochemical and molecular findings in adult patients with a confirmed diagnosis of MLIII from three treatment centres were collected...
April 27, 2018: Journal of Inherited Metabolic Disease
Chao-Hung Kao, Yih-Yuan Chen, Lian-Ren Wang, Yen-Chung Lee
N-acetyl-D-neuraminic acid (Neu5Ac) is a costly precursor for many drugs such as anti-influenza antivirals. In a previous study, a whole-cell process for Neu5Ac production was developed using a combination of two Escherichia coli cells expressing Anabaena sp. CH1 N-acetyl-D-glucosamine-2-epimerase (bage) and E. coli N-acetyl-D-neuraminic acid aldolase (nanA), respectively. In this study, we constructed a bAGE and NanA co-expression system to improve Neu5Ac production. Two recombinant E. coli strains, E. coli BL21 (DE3) pET-bage-nanA (HA) and E...
April 27, 2018: Molecular Biotechnology
Xianzhong Chen, Junbo Zhou, Lihua Zhang, Zhongji Pu, Liming Liu, Wei Shen, You Fan
N-acetyl-d-neuraminic acid (Neu5Ac) is a valuable resource that has seen increasing demand in both medicine and biotechnology. Although enzymatic systems and whole-cell biocatalysts have been developed for the synthesis of Neu5Ac, low yield and productivity still hamper the use of these methods on larger scales. We report the creation of an Escherichia coli biocatalyst for the efficient synthesis of Neu5Ac using a metabolic and protein engineering strategy. Expression of the two enzymes, N-acetyl-D-glucosamine 2-epimerase (AGE) and Neu5Ac lyase (NAL), was balanced using promoter engineering...
April 24, 2018: Metabolic Engineering
Jordi Puigdellivol, Carme Comellas Berenger, Miguel Ángel Pérez Fernández, Juan M Cowalinsky Millán, Christian Carreras Vidal, Inés Gil Gil, Julio Martínez Pagán, Borja Ruiz Nieto, Francisco Jiménez Gómez, Francesc X Comas Figuerola, María E Aguilar Hernández
This observational, open, multicenter clinical trial with a single treatment group aimed to evaluate the effectiveness of a dietary supplement whose main ingredients are hydrolyzed gelatin, chondroitin sulfate, glucosamine sulfate, and devil's claw and bamboo extracts for pain reduction and improvement of functional capacities in patients with osteoarthritis (OA) of the knee and/or hip (REDART study). In all, 130 patients with OA recruited from Spanish hospitals received the dietary supplement for 6 months...
April 27, 2018: Journal of Dietary Supplements
Sean W Bisset, Sung-Hyun Yang, Zaid Amso, Paul W R Harris, Mark L Patchett, Margaret A Brimble, Gillian E Norris
Glycocin F, a bacteriocin produced by Lactobacillus plantarum KW30, is glycosylated with two N-acetyl-d-glucosamine sugars, and has been shown to exhibit a rapid and reversible bacteriostasis on susceptible cells. The roles of certain structural features of glycocin F have not been studied to date. We report here the synthesis of various glycocin F analogues through solid-phase peptide synthesis (SPPS) and native chemical ligation (NCL), allowing us to probe the roles of different structural features of this peptide...
April 27, 2018: ACS Chemical Biology
Tao Wang, Xiao-Huan Liu, Mian-Bin Wu, Shun Ge
Bacilysin is one of the simplest antimicrobial peptides and has drawn great attention for its excellent performance against Candida albicans. In this study, the antifungal mechanism of bacilysin was investigated. The target enzyme glucosamine-6-phosphate synthase (GFA) was expressed heterologously in Escherichia coli and its inhibition by bacilysin and derivatives was studied. It was concluded that bacilysin could be hydrolyzed by a proteinase of C. albicans, and that the released product, anticapsin, then inhibited the aminotransferase activity of GFA...
April 26, 2018: Journal of Molecular Modeling
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