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Castano Roberto - - 2012
OBJECTIVES/HYPOTHESIS: The existence of nasal mucosa remodeling in allergic rhinitis is controversial. Few data are available on the dynamics of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in nasal fluid after an allergen challenge. We examined whether an immediate allergic reaction that induces nasal congestion and inflammation is ...
Grover Navdeep - - 2012
Laccase and chloroperoxidase (CPO) were separately immobilized onto multi-walled carbon nanotubes (MWNTs) and subsequently mixed with a commercial eco-friendly paint to generate biocatalytic coatings. The laccase-nanotube based paints showed >99% bactericidal activity against Escherichia coli and Staphylococcus aureus (both challenged with 10(6)CFU/mL) within 30min and >98% sporicidal activity against Bacillus ...
Kabra Akhil N - - 2012
Plants of Glandularia pulchella (Sweet) Tronc. performed decolorization of structurally different dyes to varying extent because of induction of different set of enzymes in response to specific dyes. Differential pattern of enzyme induction with respect to time was obtained for lignin peroxidase, veratryl alcohol oxidase, tyrosinase and dichlorophenolindophenol reductase during ...
Santiago R - - 2012
This study describes a method for determining cinnamyl alcohol dehydrogenase activity in sugarcane stems using RP-HPLC to elucidate their possible lignin origin. Activity is assayed using the reverse mode, the oxidation of hydroxycinnamyl alcohols into hydroxycinnamyl aldehydes. Appearance of the reaction products, coniferaldehyde and sinapaldehyde is determined by measuring absorbance ...
Vasu Prasanna - - 2012
The methylotrophic yeast Pichia pastoris is increasingly used for heterologous expression of high quality proteins in laboratory-scale (milligram) quantities. Commercially available polysaccharide-active enzyme preparations have limited applications in plant cell wall research due to their heterogeneous mix of hydrolytic activities. P. pastoris provides an ideal in vitro expression system for ...
Nandakumar Natarajan - - 2012
DMBA is a major class of potent genotoxic chemical carcinogen present in the environment and it may increase breast cancer risk. Flavonoids have been shown to have interesting biological activities in many experimental investigations. Hesperidin is one of the citrus flavonoid shown to be active against various oxidative stress mediated ...
Wang Qian - - 2011
Alcohol dehydrogenases (ADHs) from thermophilic microorganisms are interesting enzymes that have their potential applications in biotechnology and potentially provide insight into the mechanisms of action of thermo-tolerant proteins. The molecular mechanisms of ADHs under thermal stress in vivo have yet to be explored. Herein, we employed a proteomic strategy to ...
Takeda Minoru - - 2011
Bacterial strain B-009, capable of using racemic 1,2-propanediol (PD), was identified as a rapid-growing member of the genus Mycobacterium. The strain is phylogenetically related to M. gilvum, but has slightly different physiological characteristics. An NAD(+)-dependent enantioselective alcohol dehydrogenase, which acts on R-PD, was purified from the strain. The enzyme was ...
Green Sol A - - 2011
Flowers of the kiwifruit species Actinidia chinensis produce a mixture of sesquiterpenes derived from farnesyl diphosphate (FDP) and monoterpenes derived from geranyl diphosphate (GDP). The tertiary sesquiterpene alcohol (E)-nerolidol was the major emitted volatile detected by headspace analysis. Contrastingly, in solvent extracts of the flowers, unusually high amounts of (E,E)-farnesol ...
Dhillon Gurpreet Singh - - 2011
Enzyme extracts of cellulase [filter paper cellulase (FPase) and carboxymethyl cellulase (CMCase)], chitinase, and chitosanase produced by Aspergillus niger NRRL-567 were evaluated. The interactive effects of initial moisture and different inducers for FP cellulase and CMCase production were optimized using response surface methodology. Higher enzyme activities [FPase 79.24+/- 4.22 IU/gram ...
Jang Eunji - - 2011
This paper presents a simple method to fabricate a microfluidic biosensor that is able to detect substrates for H(2)O(2)-generating oxidase. The biosensor consists of three components (quantum dot-enzyme conjugates, hydrogel microstructures, and a set of microchannels) that were hierarchically integrated into a microfluidic device. The quantum dot (QD)-enzyme conjugates were ...
Egger Sigrid - - 2011
Biosynthesis of UDP-glucuronic acid by UDP-glucose 6-dehydrogenase (UGDH)5 occurs through four-electron oxidation of the C6 primary alcohol of UDP-glucose in two NAD+-dependent steps. The catalytic reaction of UGDH is thought to involve a Cys nucleophile that promotes formation of a thiohemiacetal enzyme intermediate in the course of the first oxidation ...
Nicolau Eduardo - - 2011
Diamond nanoparticles are considered a biocompatible material mainly due to their non-cytotoxicity and remarkable cellular uptake. Model proteins such as cytochrome c and lysozyme have been physically adsorbed onto diamond nanoparticles, proving it to be a suitable surface for high protein loading. Herein, we explore the non-covalent immobilization of the ...
Jain Rachit - - 2011
ABSTRACT: BACKGROUND: With the increasing consumption of fossil fuels, the question of meeting the global energy demand is of great importance in the near future. As an effective solution, production of higher alcohols from renewable sources by microorganisms has been proposed to address both energy crisis and environmental concerns. Higher ...
Brenna Elisabetta - - 2011
To overcome the usually low productivities of the C[double bond, length as m-dash]C bond bioreduction of α,β-unsaturated aldehydes we combined the in situ substrate feeding product removal (SFPR) technology with a cascade system comprising an isolated ene-reductase and a chemoselective alcohol dehydrogenase.
Chong Richard - - 2011
In order to rapidly and simultaneously quantify and screen trace levels of multiple biomarkers in a single sample, rapid 1,1'-oxalyldiimidazole chemiluminescence (ODI CL) was applied as a biosensor of immunoassays using various enzymes such as alkaline phosphatase (ALP) and horseradish peroxidise (HRP). (1) Fluorescein was formed from the reaction of ...
Rocha-Martin Javier - - 2011
ABSTRACT: BACKGROUND: The number of biotransformations that use nicotinamide recycling systems is exponentially growing. For this reason one of the current challenges in biocatalysis is to develop and optimize more simple and efficient cofactor recycling systems. One promising approach to regenerate NAD+ pools is the use of NADH-oxidases that reduce ...
Jin Peng - - 2011
In this study, an esterase, designated EstC23, was isolated from a soil metagenomic library. The protein was amenable to overexpression in Escherichia coli under control of the T7 promoter, resulting in expression of the active, soluble protein that constituted 30% of the total cell protein content. This enzyme showed optimal ...
Sheldon Roger A - - 2011
In this tutorial review, the fundamental concepts underlying the principles of green and sustainable chemistry - atom and step economy and the E factor - are presented, within the general context of efficiency in organic synthesis. The importance of waste minimisation through the widespread application of catalysis in all its ...
Willis Robert M - - 2011
Fatty alcohols are of interest as a renewable feedstock to replace petroleum compounds used as fuels, in cosmetics, and in pharmaceuticals. One biological approach to the production of fatty alcohols involves the sequential action of two bacterial enzymes: (i) reduction of a fatty acyl-CoA to the corresponding fatty aldehyde catalyzed ...
Timpson Leanne M - - 2011
Haloarchaeal alcohol dehydrogenases are of increasing interest as biocatalysts in the field of white biotechnology. In this study, the gene adh12 from the extreme halophile Haloarcula marismortui (HmADH12), encoding a 384 residue protein, was cloned into two vectors: pRV1 and pTA963. The resulting constructs were used to transform host strains ...
Liu Xu - - 2011
Gluconobacter oxydans enable to oxidize sugars and polyols incompletely to corresponding materials with potential industrial applications, containing around 75 putative dehydrogenases. One of these putative dehydrogenases, Gox2181, was cloned and expressed in Escherichia coli BL21 (DE3), and its X-ray crystal structure was determined to a resolution of 1.8Å. Gox2181 formed ...
Amann Philipp M - - 2011
Disturbances in vitamin A metabolism are an important attribute of some cancer cells. Most evidence point that these disturbances lead to decreasing of the retinoic acid concentration in tumor cells. Up to now, in benign and malignant skin cells the features of vitamin A metabolism with its participating enzymes are ...
Hofvander Per - - 2011
The reduction of acyl-CoA or acyl-ACP to fatty alcohol occurs via a fatty aldehyde intermediate. In prokaryotes this reaction is thought to be performed by separate enzymes for each reduction step while in eukaryotes these reactions are performed by a single enzyme without the release of the intermediate fatty aldehyde. ...
Rocha-Martín Javier - - 2011
The use of dehydrogenases in asymmetric chemistry has exponentially grown in the last decades facilitated by the genome mining. Here, a new short-chain alcohol dehydrogenase from Thermus thermophilus HB27 has been expressed, purified, characterized and stabilized by immobilization on solid supports. The enzyme catalyzes both oxidative and reductive reactions at ...
Sukhirun N - - 2011
The application of insecticides to control oriental fruit fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae), is a principal component of the current management of these fruit flies. However, we evaluated four extracts of Alpinia galanga Wild Linn (Zingiberaceae) rhizomes against adult flies and found hexane and ethanol extracts to be most ...
Cha Jae-Young - - 2011
Arginine possesses advantageous pharmacological properties such as liver injury protection. We have previously shown that the arginine stimulated the activities of commercial alcohol dehydrogenase (ADH, EC 1.1.1.1) and acetaldehyde dehydrogenase (ALDH, EC 1.2.1.10) enzymes in vitro experiment. We therefore examined on the activities, zymogram staining intensity, and protein expression of ...
Liu Jia - - 2011
A biosensor based on Trametes versicolor laccase (Lac) was developed for the determination of phenolic compounds. The biosensor was prepared by in situ electrospinning of a mixture of polyvinyl alcohol (PVA), Lac, PEO-PPO-PEO (F108) and gold nanoparticles (Au NPs), where F108 was used as an enzyme stabilizing additive and Au ...
Dutta Arijita - - 2011
Fructansucrase and fructan produced from Lactobacillus fermentum AKJ15 were isolated from seeds of Kodo ko jaanr, a fermented mild-alcoholic beverage prepared in North East India. The strain was identified by 16S rRNA gene sequence analysis and biochemical characterization. The strain displayed maximum fructansucrase activity of 4.3 U/ml (1.02 U/mg) at 28°C at ...
Varbanova Marina - - 2011
To elucidate the genetic and biochemical regulation of elicitor-induced p-coumaraldehyde accumulation in plants, we undertook a multi-faceted approach to characterize the metabolic flux through the phenylpropanoid pathway, via the characterization and chemical analysis of the metabolites in the p-coumaryl, coniferyl and sinapyl alcohol branches of this pathway. Herein, we report ...
Manavalan Arulmani - - 2011
The basidiomycete fungi such as Phanerochaete chrysosporium secrete large amount of hydrolytic and oxidative enzymes and degrade lignocellulosic biomass. The lignin depolymerizing proteins were extensively studied, but cellulose, hemicellulose and pectin hydrolyzing enzymes were poorly explored. In this study P. chrysosporium was grown in cellulose, lignin and mixture of cellulose ...
Nishimura Motohiro - - 2011
We purified two isozymes of coniferyl alcohol dehydrogenase (CADH I and II) to homogeneity from cell-free extracts of Streptomyces sp. NL15-2K. The apparent molecular masses of CADH I and II were determined to be 143 kDa and 151 kDa respectively by gel filtration, whereas their subunit molecular masses were determined ...
Dobslaw Daniel - - 2011
A strain Rhodococcus sp. OCT 10 DSM 45596(T), exhibiting 99.9% of 16S rDNA identity with Rhodococcus wratislaviensis NCIMB 13082, was isolated from a soil sample. The strain completely mineralised 2-chlorotoluene, 2-bromotoluene, o-xylene, benzyl alcohol and benzoate. In contrast, 2-fluorotoluene was only partially mineralised. By GC-MS and (1)H-NMR analyses, 4-chloro-3-methylcatechol was ...
Jordan Douglas B - - 2011
An effective means of relieving the toxicity of furan aldehydes, furfural (FFA) and 5-hydroxymethylfurfural (HMF), on fermenting organisms is essential for achieving efficient fermentation of lignocellulosic biomass to ethanol and other products. Ari1p, an aldehyde reductase from Saccharomyces cerevisiae, has been shown to mitigate the toxicity of FFA and HMF ...
Akıllıoglu Halise Gül - - 2011
5-Hydroxymethyl furfural (HMF) may occur in malt in high quantities depending on roasting conditions. However, the HMF content of different types of beers is relatively low, indicating its potential for degradation during fermentation. This study investigates the degradation kinetics of HMF in wort during fermentation by Saccharomyces cerevisiae. The results ...
Rawal Rachna - - 2011
Laccase purified from Ganoderma sp. was immobilized covalently onto electrochemically deposited silver nanoparticles (AgNP)/carboxylated multiwalled carbon nanotubes (cMWCNT)/polyaniline (PANI) layer on the surface of gold (Au) electrode. A polyphenol biosensor was fabricated using this enzyme electrode (laccase/AgNP/cMWCNT/PANI/Au electrode) as the working electrode, Ag/AgCl as the reference electrode, and platinum (Pt) ...
Buchhaupt Markus - - 2011
Green notes are substances that characterize the aroma of freshly cut grass, cucumbers, green apples, and foliage. In plants, they are synthesized by conversion of linolenic or linoleic acid via the enzymes lipoxygenase (LOX) and hydroperoxide lyase (HPL) to short-chained aldehydes. Current processes for production of natural green notes rely ...
Badenes Sara M - - 2011
The kinetics of the enzymatic transesterification between a mixture of triglycerides (oils) and methanol for biodiesel production in a bis(2-ethylhexyl) sodium sulfosuccinate (AOT)/isooctane reversed micellar system, using recombinant cutinase from Fusarium solani pisi as a catalyst, was investigated. In order to describe the results that were obtained, a mechanistic scheme ...
Kannangara Rubini - - 2011
Cassava (Manihot esculenta) contains two cyanogenic glucosides, linamarin and lotaustralin, biosynthesized from L-valine and L-isoleucine, respectively. In this study, cDNAs encoding two UGT paralogs, assigned UGT85K4 and UGT85K5, have been isolated from cassava. The paralogs display 96% amino acid identity and belong to a family containing cyanogenic glucoside-specific UGTs from ...
Müller Christian E - - 2011
Acyl transfer is at the heart of functional-group transfers utilized both in nature and in the chemical laboratory. Acylations are part of the natural assembly machinery for the generation of complex molecules and for energy transport in biological systems. The recognition of covalent acyl-enzyme intermediates led to both mechanistic studies ...
Dekishima Yasumasa - - 2011
An <i>Escherichia coli</i> strain was engineered to synthesize 1-hexanol from glucose by extending the coenzyme A (CoA)-dependent 1-butanol synthesis reaction sequence catalyzed by exogenous enzymes. The C4-acyl-CoA intermediates were first synthesized via acetyl-CoA acetyltransferase (AtoB), 3-hydroxybutyryl-CoA dehydrogenase (Hbd), crotonase (Crt), and trans-enoyl-CoA reductase (Ter) from various organisms. The butyryl-CoA synthesized ...
Kourist Robert - - 2011
The enzymatic preparation of optically pure tertiary alcohols under sustainable conditions has received much attention. The conventional chemical synthesis of these valuable building blocks is still hampered by the use of harmful reagents such as heavy metal catalysts. Successful examples in biocatalysis used esterases, lipases, epoxide hydrolases, halohydrin dehalogenases, thiamine ...
Sellami Mohamed - - 2011
ABSTRACT: BACKGROUND: Waxes are esters of long-chain fatty acids and long-chain alcohols. Their principal natural sources are animals (sperm whale oil) and vegetables (jojoba) which are expensive and not easily available. Wax esters synthesized by enzymatic transesterification, using palm stearin as raw material, can be considered as an alternative to ...
Ni Yan - - 2011
A carbonyl reductase gene (yueD) from Bacillus sp. ECU0013 was heterologously overexpressed in Escherichia coli, and the encoded protein (BYueD) was purified to homogeneity and characterized. The NADPH-dependent reductase showed a broad substrate spectrum towards different aromatic ketones, and α- and β-ketoesters. Although the enantioselectivity was high to moderate for ...
Kawano Shigeru - - 2011
A novel (R)-specific alcohol dehydrogenase (AFPDH) produced by Candida maris IFO10003 was purified to homogeneity by ammonium sulfate fractionation, DEAE-Toyopearl, and Phenyl-Toyopearl, and characterized. The relative molecular mass of the native enzyme was found to be 59,900 by gel filtration, and that of the subunit was estimated to be 28,900 ...
Nagel Zachary D - - 2011
A growing body of data supports a role for protein motion in enzyme catalysis. In particular, the ability of enzymes to sample catalytically relevant conformational substates has been invoked to model kinetic and spectroscopic data. However, direct experimental links between rapidly interconverting conformations and the chemical steps of catalysis remain ...
Okamoto Sho - - 2011
The rhizome oil of Zingiber zerumbet Smith contains an exceptionally high content of sesquiterpenoids with zerumbone, a predominating potential multi-anticancer agent. Biosynthetic pathways of zerumbone have been proposed, and two genes ZSS1 and CYP71BA1 that encode the enzymes catalyzing the first two steps have been cloned. In this paper, we ...
Kołek Teresa - - 2011
The course of transformation of DHEA, androstenediol and epiandrosterone in Mortierella isabellina AM212 culture was investigated. The mentioned substrates underwent effective hydroxylation; 5-ene substrates - DHEA and androstenediol - were transformed into a mixture of 7α- and 7β- allyl alcohols, while epiandrosterone was converted into 7α- (mainly), 11α- and 9α- ...
Dhillon G S - - 2011
Studies were carried out for β-glucosidase production using apple pomace (AP) in solid-state fermentation using 2(4) factorial design and response surface methodology. The influence of four independent variables including initial moisture level and inducers [veratryl alcohol (VA), lactose (LAC) and copper sulfate (CS)] was studied. The experimental design showed that ...
Kang Chul-Hyung - - 2011
ABSTRACT: BACKGROUND: Among the vast microbial genomic resources now available, most microbes are unculturable in the laboratory. A culture-independent metagenomic approach is a novel technique that circumvents this culture limitation. For the screening of novel lipolytic enzymes, a metagenomic library was constructed from compost, and the clone of estCS2 was ...
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