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Liu Ze - - 2012
Multiphase acid-catalyzed oxidation by hydrogen peroxide has been suggested to be a potential route to secondary organic aerosol formation from isoprene and its gas-phase oxidation products, but the lack of kinetics data significantly limited the evaluation of this process in the atmosphere. Here we report the first measurement of the ...
Xiong Mingyong - - 2012
Depleting oil reserves and growing environmental concerns have necessitated the development of sustainable processes to fuels and chemicals. Here we have developed a general metabolic platform in E. coli to biosynthesize carboxylic acids. By engineering selectivity of 2-ketoacid decarboxylases and screening for promiscuous aldehyde dehydrogenases, synthetic pathways were constructed to ...
Zhan Tianzuo - - 2012
Long chain acyl-CoA synthetases are essential enzymes of lipid metabolism, and have also been implicated in the cellular uptake of fatty acids. It is controversial if some or all of these enzymes have an additional function as fatty acid transporters at the plasma membrane. The most abundant acyl-CoA synthetases in ...
Maiti Munmun - - 2011
Nucleoside phosphoramidates (NPs) are a class of nucleotide analogues that has been developed as potential antiviral/antitumor prodrugs. Recently, we have shown that some amino acid nucleoside phosphoramidates (aaNPs) can act as substrates for viral polymerases like HIV-1 RT. Herein, we report the synthesis and hydrolysis of a series of new aaNPs, ...
Roughley Stephen D - - 2011
We describe here our attempts to optimise the human fatty acid amide hydrolase (FAAH) inhibition and physicochemical properties of our previously reported tetrasubstituted azetidine urea FAAH inhibitor, VER-156084. We describe the SAR of a series of analogues and conclude with the demonstration of in vivo dose-dependant FAAH inhibition in an ...
Bai Bing - - 2011
Seeds in the seed-bank experience diurnal cycles of imbibition followed by complete dehydration. These conditions pose a challenge to the regulation of germination. The effect of recurring hydration-dehydration (Hy-Dh) cycles were tested on seeds from four Arabidopsis thaliana accessions [Col-0, Cvi, C24 and Ler]. Diurnal Hy-Dh cycles had a detrimental ...
Hoefig Carolin S - - 2011
Thyronamines (TAM), recently described endogenous signaling molecules, exert metabolic and pharmacological actions partly opposing those of the thyromimetic hormone T(3). TAM biosynthesis from thyroid hormone (TH) precursors requires decarboxylation of the l-alanine side chain and several deiodination steps to convert e.g. l-thyroxine (T(4)) into the most potent 3-T(1)AM. Aromatic l-amino ...
Baggott Joseph E - - 2011
Several reports suggest that folate has a procarcinogenic effect. Folate has a unique role because its coenzymes are needed for de novo purine and thymine nucleotide biosynthesis. Antifolates, such as methotrexate, are used in cancer treatment. Using a meta-analysis weighted for the duration of folic acid (pteroylglutamic acid) supplementation, we ...
Liu Lian Jin - - 2011
Novel 5'-norcarbocyclic adenosine phosphonic acid analogues with 6'-electropositive moiety such as spirocyclopropane were designed and synthesized from the commercially available diethylmalonate 5. Regioselective Mitsunobu reaction proceeded in the presence of an allylic functional group at a low reaction temperature in polar cosolvent [dimethylformamide (DMF)/1,4-dioxane] to give purine analogue 15. To ...
Rivas-Sendra Alba - - 2011
Aims:  To determine the inhibitory effect of phenolic compounds on Lactobacillus casei BL23, the role of two component signal transduction systems (TCS), and the response of Lact. casei BL23 to p-coumaric acid. Methods and Results:  Growth of Lact. casei BL23 and 17 derivative strains defective in each TCS harboured by ...
Chen Jianshun - - 2011
Listeria monocytogenes is a foodborne pathogen causing listeriosis. Acid is one of the most frequently stresses that foodborne pathogens encounter. The ability to survive and proliferate in acidic environments is a prerequisite for its infection. However, there is limited knowledge about the molecular basis of adaption of L. monocytogenes to ...
Ishibashi Matsujiro - - 2011
We have previously reported that amino-terminal extension sequence containing hexa-His facilitated refolding and assembly of hexameric nucleoside diphosphate kinase from extremely halophilic archaeon Halobacterium salinarum (NDK). In this study, we made various mutations in both the tag sequence and within NDK molecule. SerNDK, in which hexa-His was replaced with hexa-Ser, ...
Iqbal Aman - - 2011
Structural and biochemical analyses reveal how ornithine acetyl-transferases catalyse the reversible transfer of an acetyl-group from a basic (ornithine) to an acidic (glutamate) amino acid by employing a common mechanism involving an acetyl-enzyme intermediate but using different side chain binding modes.
Pan Qiu-Hong - - 2011
The pleasantly fruity and floral 2-phenylethanol are a dominant aroma compound in post-ripening 'Vidal blanc' grapes. However, to date little has been reported about its synthetic pathway in grapevine. In the present study, a full-length cDNA of VvAADC (encoding aromatic amino acid decarboxylase) was firstly cloned from the berries of ...
Onursal Mehmet - - 2011
The aim of the present study was to prepare (99m)Tc-folate-glucaric acid and investigate the radiopharmaceutical potential for tumors imaging that over express folate receptor. Folate-glucaric acid was synthesized and the synthesized folate conjugate was confirmed with (1)H NMR and LC-MS/MS methods. Folate-glucaric acid was labeled with (99m)Tc, and its radiolabelling ...
Guseva Natalya V - - 2011
A key player in prostate cancer development and progression is the androgen receptor (AR). Tumor-associated lipogenesis can protect cancer cells from carcinogenic- and therapeutic-associated treatments. Increased synthesis of fatty acids and cholesterol is regulated by androgens through induction of several genes in androgen-responsive cancer cells. Acetyl-CoA-carboxylase-α (ACCA) is a key ...
Selhub Jacob - - 2011
Folic acid fortification of cereal grains was introduced in many countries to prevent neural tube defect occurrence. The metabolism of folic acid and vitamin B12 intersect during the transfer of the methyl group from 5-methyltetrahydrofolate to homocysteine catalyzed by B12-dependent methioine synthase. Regeneration of tetrahydrofolate via this reaction makes it ...
Lange Christian - - 2011
Corynebacterium glutamicum possesses export systems for various amino acids including BrnFE, a two-component export system for l-methionine and the branched-chain amino acids l-valine, l-isoleucine and l-leucine. A gene for a putative transcriptional regulator of the Lrp family is transcribed divergently to the brnFE operon and is required for l-isoleucine export. ...
Kingston Anthony W - - 2011
Bacteria respond to physical and chemical stresses that affect the integrity of the cell wall and membrane by activating an intricate cell envelope stress response. The ability of cells to regulate the biophysical properties of the membrane by adjusting fatty acid composition is known as homeoviscous adaptation. Here, we identify ...
Ahrens Katherine - - 2011
BACKGROUND:: The US Food and Drug Administration mandated that enriched grain products be fortified with folic acid by 1998. We evaluated whether intake of folic acid from supplements and diet was associated with a reduction in spina bifida in the setting of folic acid fortification. METHODS:: Data were collected as ...
Bhamidi Suresh - - 2011
The cell wall of mycobacteria consists of an outer membrane, analogous to that of gram-negative bacteria, attached to the peptidoglycan (PG) via a connecting polysaccharide arabinogalactan (AG). Although the primary structure of these components is fairly well deciphered, issues such as the coverage of the PG layer by covalently attached ...
Vandeventer Peter E - - 2011
Molecular detection of microorganisms requires microbial cell disruption to release nucleic acids. Sensitive detection of thick-walled microorganisms such as Bacillus spores and Mycobacterium cells typically necessitates mechanical disruption through bead beating or sonication, using benchtop instruments that require line power. Miniaturized, low-power, battery-operated devices are needed to facilitate mechanical pathogen ...
Hellwig Michael - - 2011
In glycation reactions, the side chains of protein-bound nucleophilic amino acids such as lysine and arginine are post-translationally modified to a variety of derivatives also known as Maillard reaction products (MRPs). Considerable amounts of MRPs are taken up in food. Here we have studied the interactions of free and dipeptide-bound ...
Carvalho Ana Lúcia - - 2011
Trehalose accumulation is a common cell defense strategy against a variety of stressful conditions. In particular, our team detected high levels of trehalose in Propionibacterium freudenreichii in response to acid stress, a result that led to the idea that endowing Lactococcus lactis with the capacity to synthesize trehalose could improve ...
Berkovitch-Luria Gili - - 2011
Herein we describe a series of multifunctional 5-aminolevulinic-acid (ALA) prodrugs for photodynamic dependent and independent cancer therapy (PDT). We studied the cell-death mechanisms in glioblastoma U251 cells treated with four ALA-prodrugs: (1) AlaAcBu, that releases ALA, acetaldehyde, and butyric acid; (2) AlaFaBu, that releases ALA, formaldehyde, and butyric acid; (3) ...
Sakamoto Toshio - - 2011
The aquatic cyanobacterium Nostoc verrucosum forms macroscopic colonies, which consist of both cellular filaments and massive extracellular matrix material. In this study, the physiological features of N. verrucosum were investigated and compared with those of the anhydrobiotic cyanobacterium Nostoc commune. N. verrucosum cells were sensitive to desiccation but tolerant of ...
Ito Y - - 2011
As new BNCT reagents, we designed and synthesized dopamine analogues containing phenylboronic acid group, N-3,4-dihydroxyphenethyl-4-dihydroxyborylbenzamide (dopamine-PCBA) and N-[2-(3,4-dihydroxyphenetyl)ethyl]-3-(4-dihydroxyborylphenyl)promionamide (dopamine-CEBA). The efficacies of these compounds have not been investigated for biological samples. Therefore we have carried out experiments with cultured tumor cells and tumor-bearing mice, and evaluated possibility of these compounds ...
Musa C V CV Dipartimento di Biochimica e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Naples, - - 2012
The objective of the study was to look for uncoupling protein 3 (UCP3) gene variants in early-onset severe childhood obesity and to determine their effect on long-chain fatty acid oxidation and triglyceride storage. We identified four novel mutations in the UCP3 gene (V56M, A111V, V192I and Q252X) in 200 children ...
Barbarić Monika - - 2011
AIM OF THE STUDY: Cytotoxic effect of various ethanol propolis extractions was assessed on the cervical tumor cell line (HeLa) and compared with their phenolic acids and flavonoid composition. MATERIALS AND METHODS: Twenty samples of raw propolis were collected from 17 localities of Croatia (I-XVII), 2 of Bosnia and Hercegovina ...
Pandey Deepak - - 2011
Acyltransferase activity of amidase from Bacillus sp. APB-6 was enhanced (24U) by multiple feedings of N-methylacetamide (70mM) into the production medium. Hyperinduced whole resting cells of Bacillus sp. APB-6 corresponding to 4g/L (dry cell weight), when treated with 10mM DTT (dithiothreitol) resulted in 93% molar conversion of acetamide (300mM) to ...
Liu Xinyao - - 2011
To avoid costly biomass recovery in photosynthetic microbial biofuel production, we genetically modified cyanobacteria to produce and secrete fatty acids. Starting with introducing an acyl-acyl carrier protein thioesterase gene, we made six successive generations of genetic modifications of cyanobacterium Synechocystis sp. PCC6803 wild type (SD100). The fatty acid secretion yield ...
Morosini Vincent - - 2011
This study examined the in vitro potential of bioconjugated quantum dots (QDs) as photosensitizers for photodynamic therapy (PDT). According to our previous approaches using photosensitizers, folic acid appears to be an optimal targeting ligand for selective delivery of attached therapeutic agents to cancer tissues. We synthesized hydrophilic near infrared emitting ...
Yue Zhilian - - 2011
In this work, polydimethylsiloxane was activated with oxygen plasma and treated with silanes bearing ethylene imine units. Hyaluronic acid was then grafted covalently onto the aminated surfaces. The influence of silane structure on surface amination was assessed and the influence of the modification on surface physiochemical properties and protein adsorption ...
Murray John W - - 2011
Sodium taurocholate-cotransporting polypeptide (ntcp) is considered to be a major determinant of bile acid uptake into hepatocytes. However, the regulation of ntcp and the degree that it participates in the accumulation of specific substrates are not well understood. We utilized fluorescent bile acid derivatives and direct quantitation of fluorescent microscopy ...
Oya Manami - - 2011
Amino acids such as L-glutamate and L-arginine are potent stimuli for insulin secretion from pancreatic β-cells. However, the precise molecular mechanisms of amino acid-induced insulin secretion have only partly understood. In this study, we show here that mouse pancreatic β-cell line MIN6 cells expressed amino acid taste receptor (heterodimer of ...
Yeh Kwo-Yih - - 2011
BACKGROUND & AIMS:: Ferroportin (Fpn) is a multiple transmembrane protein required for iron export into the systemic circulation, in cooperation with hephaestin (Heph). Despite the importance of Fpn in iron transport, there is controversy about its topology and functional state upon interaction with Heph. METHODS:: The topology of Fpn was ...
Ku Chai Siah - - 2011
Adenosine triphosphate-binding cassette transporter A1 (ABCA1) plays a critical role in the formation and metabolism of high-density lipoproteins (HDLs). Adenosine triphosphate-binding cassette transporter A1 in the liver and small intestine, in particular, accounts for approximately 90% of plasma HDL cholesterol. Therefore, any alterations in the hepatic and intestinal expression of ...
Wiefel Lars - - 2011
Synthesis of cyanophycin (multi-L: -arginyl-poly-L: -aspartic acid, CGP) in recombinant organisms is an important option to obtain sufficiently large amounts of this polymer with a designed composition for use as putative precursors for biodegradable technically interesting chemicals. Therefore, derivates of CGP, harbouring a wider range of constituents, are of particular ...
Igarashi Mamoru - - 2011
Glucosamine (GlcN) has been widely used to treat osteoarthritis (OA) in humans. However, its chondroprotective action on the joint is poorly understood. In this study, to elucidate the chondroprotective action of GlcN, we examined the effects of GlcN-derivatives (GlcN and N-acetyl-D-glucosamine) and uronic acids (D-glucuronic acid and D-galacturonic acid) (0.1-1 mM) ...
Shashkov Alexander S - - 2011
The cell wall of Bacillus subtilis VKM B-762 contains, along with 1,5-poly[4-O-(2-acetamido-2-deoxy-β-d-glucopyranosyl)ribitol phosphate], a novel type of glycopolymer involving three types of inter-monomeric bonds in the repeating unit, viz., amide, glycosidic and phosphodiester: Such a structural pattern of natural glycopolymers has been hitherto unknown. This polymer represents a novel type ...
Son Young-Dok - - 2011
Therapeutic glycoproteins with exposed galactose residues are cleared rapidly from the bloodstream by asialoglycoprotein receptors in hepatocytes. Various approaches have been used to increase content of sialic acid, which occupies terminal sites of N- or O-linked glycans and thereby increases half-life of therapeutic glycoproteins. We enhanced sialylation of human erythropoietin ...
Chen Guan-Yu - - 2011
A new conjugated polymer, PDTTTPD, comprising 2,5-di(thiophen-2-yl)thieno[3,2-b]thiophene and thieno[3,4-c]pyrrole-4,6-dione units, exhibits high crystallinity and excellent thermal stability. A device incorporating PDTTTPD and [6,6]-phenyl-C(71)-butyric acid methyl ester (1 : 1, w/w) exhibited a power conversion efficiency of 5.1%.
Li Xu-Yuan - - 2011
To demonstrate the effect of zoledronic acid in proliferation, invasion, and migration of human nasopharyngeal carcinoma cell HNE-1 and explore the potential role of VEGF, MMP-2, and MMP-9 proteins in vitro. Human nasopharyngeal carcinoma cell HNE-1 was exposed to various concentrations (0-40 μmol/l) of zoledronic acid. Zoledronic acid inhibited proliferation of ...
Huang Yanmin - - 2011
Using cholic acid and deoxycholic acid as starting materials, a series of 3-aza-A-homo-4-one bile acid and 7-deoxycholic acid derivatives were synthesized by the esterification, oxidation, reduction, oximation and Beckman rearrangement etc. The cytotoxicity of the synthesized compounds against MGC 7901 (human ventriculi carcinoma cell line), hela (human cervical carcinoma cell ...
Rodrigues Rita C L B - - 2011
Corn stover that had been treated with vapor-phase diethyl oxalate released a mixture of mono- and oligosaccharides consisting mainly of xylose and glucose. Following overliming and neutralization, a D: -xylulokinase mutant of Pichia stipitis, FPL-YS30 (xyl3-∆1), converted the stover hydrolysate into xylitol. This research examined the effects of phosphoric or ...
Sauter Alexander - - 2011
PURPOSE: Restenosis is still one of the major limitations after angioplasty. A therapeutic treatment combining β-irradiation and pharmacologic cyclooxygenase-2 inhibition was employed to study the impact on vascular smooth muscle cells (SMCs). MATERIALS AND METHODS: The effects of meclofenamic acid in combination with yttrium-90 ((90)Y) on cell growth, clonogenic activity, ...
Nualkaekul Sawaminee - - 2011
The aim of the work was to study the survival of Lactobacillus plantarum NCIMB 8826 in model solutions and develop a mathematical model describing its dependence on pH, citric acid and ascorbic acid. A Central Composite Design (CCD) was developed studying each of the three factors at five levels within ...
Almeida Domingos P F - - 2011
Autolysis of cell walls from polygalacturonase (PG)-antisense tomato fruit was studied in a conventional buffer designed to maximize the catalytic activity of PG (30mM sodium acetate, 150mM NaCl, pH 4.5), and in solutions mimicking the pH and mineral composition of the fruit apoplast at the mature-green and ripe stages. Autolytic ...
Song Penghong - - 2011
Kir4.1 channels were found to colocalize with the H(+)/K(+)-ATPase throughout the parietal cell (PC) acid secretory cycle. This study was undertaken to explore their functional role. Acid secretory rates, electrophysiological parameters, PC ultrastructure, and gene and protein expression were determined in gastric mucosae of 7-8-day-old Kir4.1-deficient mice and WT littermates. ...
Ge Fei - - 2011
The major objective of the present study was to investigate the role of iron and manganese on the formation of haloacetic acids (HAAs) when algae are chlorinated at different pHs. The results showed that both iron and manganese can reduce the yields of dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) ...
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