keyword
MENU ▼
Read by QxMD icon Read
search

PQQ

keyword
https://www.readbyqxmd.com/read/27876710/enhancement-of-1-3-dihydroxyacetone-production-from-gluconobacter-oxydans-by-combined-mutagenesis
#1
Xi Lin, Sha Liu, Guangrong Xie, Jing Chen, Penghua Li, Jianhua Chen
Wild strain L-6 was subjected to combined mutagenesis, including UV irradiation, atmospheric and room temperature plasma, and ion beam implantation, to increase the yield of 1,3-dihydroxyacetone (DHA). With application of a high-throughput screening method, mutant Gluconobacter oxydans I-2-239 with a DHA productivity of 103.5 g/l in flask-shake fermentation was finally obtained with the starting glycerol concentration of 120 g/l, which was 115.7% higher than the wild strain. The cultivation time also decreased from 54 h to 36 h...
November 28, 2016: Journal of Microbiology and Biotechnology
https://www.readbyqxmd.com/read/27849146/membrane-bound-glycerol-dehydrogenase-catalyzes-oxidation-of-d-pentonates-to-4-keto-d-pentonates-d-fructose-to-5-keto-d-fructose-and-d-psicose-to-5-keto-d-psicose
#2
Yoshitaka Ano, Roque A Hours, Yoshihiko Akakabe, Naoya Kataoka, Toshiharu Yakushi, Kazunobu Matsushita, Osao Adachi
A novel oxidation of D-pentonates to 4-keto-D-pentonates was analyzed with Gluconobacter thailandicus NBRC 3258. D-Pentonate 4-dehydrogenase activity in the membrane fraction was readily inactivated by EDTA and it was reactivated by the addition of PQQ and Ca(2+). D-Pentonate 4-dehydrogenase was purified to two different subunits, 80 and 14 kDa. The absorption spectrum of the purified enzyme showed no typical absorbance over the visible regions. The enzyme oxidized D-pentonates to 4-keto-D-pentonates at the optimum pH of 4...
November 16, 2016: Bioscience, Biotechnology, and Biochemistry
https://www.readbyqxmd.com/read/27836608/an-improved-glycerol-biosensor-with-an-au-fes-nad-glycerol-dehydrogenase-anode
#3
Aishwarya Mahadevan, Sandun Fernando
An improved glycerol biosensor was developed via direct attachment of NAD(+)-glycerol dehydrogenase coenzyme-apoenzyme complex onto supporting gold electrodes, using novel inorganic iron (II) sulfide (FeS)-based single molecular wires. Sensing performance factors, i.e., sensitivity, a detection limit and response time of the FeS and conventional pyrroloquinoline quinone (PQQ)-based biosensor were evaluated by dynamic constant potential amperometry at 1.3V under non-buffered conditions. For glycerol concentrations ranging from 1 to 25mM, a 77% increase in sensitivity and a 53% decrease in detection limit were observed for the FeS-based biosensor when compared to the conventional PQQ-based counterpart...
October 31, 2016: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/27805779/a-nernstian-biosupercapacitor
#4
Dmitry Pankratov, Felipe Conzuelo, Piyanut Pinyou, Sabine Alsaoub, Wolfgang Schuhmann, Sergey Shleev
We propose the very first "Nernstian biosupercapacitor", a biodevice based on only one redox polymer: poly(vinyl imidazole-co-allylamine)[Os(bpy)2 Cl], and two biocatalysts. At the bioanode PQQ-dependent glucose dehydrogenase reduces the Os(3+) moieties at the polymer to Os(2+) shifting the Nernst potential of the Os(3+) /Os(2+) redox couple to negative values. Concomitantly, at the biocathode the reduction of O2 by means of bilirubin oxidase embedded in the same redox polymer leads to the oxidation of Os(2+) to Os(3+) shifting the Nernst potential to higher values...
November 2, 2016: Angewandte Chemie
https://www.readbyqxmd.com/read/27760187/genetically-engineered-escherichia-coli-nissle-1917-synbiotics-reduce-metabolic-effects-induced-by-chronic-consumption-of-dietary-fructose
#5
Chaudhari Archana Somabhai, Ruma Raghuvanshi, G Nareshkumar
AIMS: To assess protective efficacy of genetically modified Escherichia coli Nissle 1917 (EcN) on metabolic effects induced by chronic consumption of dietary fructose. MATERIALS AND METHODS: EcN was genetically modified with fructose dehydrogenase (fdh) gene for conversion of fructose to 5-keto-D-fructose and mannitol-2-dehydrogenase (mtlK) gene for conversion to mannitol, a prebiotic. Charles foster rats weighing 150-200 g were fed with 20% fructose in drinking water for two months...
2016: PloS One
https://www.readbyqxmd.com/read/27638737/-1-h-13-c-and-15-n-resonance-assignments-and-secondary-structure-information-for-methylobacterium-extorquens-pqqd-and-the-complex-of-pqqd-with-pqqa
#6
Robert L Evans, John A Latham, Judith P Klinman, Carrie M Wilmot, Youlin Xia
The ribosomally synthesized and post-translationally modified peptide (RiPP), pyrroloquinoline quinone (PQQ), is a dehydrogenase cofactor synthesized by, but not exclusively used by, certain prokaryotes. RiPPs represent a rapidly expanding and diverse class of natural products-many of which have therapeutic potential-and the biosynthetic pathways for these are gaining attention. Five gene products from the pqq operon (PqqA, PqqB, PqqC, PqqD, and PqqE) are essential for PQQ biosynthesis. The substrate is the peptide PqqA, which is presented to the radical SAM enzyme PqqE by the small protein PqqD...
October 2016: Biomolecular NMR Assignments
https://www.readbyqxmd.com/read/27625643/determination-of-dehydrogenase-activities-involved-in-d-glucose-oxidation-in-gluconobacter-and-acetobacter-strains
#7
Florencia Sainz, María Jesús Torija, Minenosuke Matsutani, Naoya Kataoka, Toshiharu Yakushi, Kazunobu Matsushita, Albert Mas
Acetic acid bacteria (AAB) are known for rapid and incomplete oxidation of an extensively variety of alcohols and carbohydrates, resulting in the accumulation of organic acids as the final products. These oxidative fermentations in AAB are catalyzed by PQQ- or FAD- dependent membrane-bound dehydrogenases. In the present study, the enzyme activity of the membrane-bound dehydrogenases [membrane-bound PQQ-glucose dehydrogenase (mGDH), D-gluconate dehydrogenase (GADH) and membrane-bound glycerol dehydrogenase (GLDH)] involved in the oxidation of D-glucose and D-gluconic acid (GA) was determined in six strains of three different species of AAB (three natural and three type strains)...
2016: Frontiers in Microbiology
https://www.readbyqxmd.com/read/27573017/pyrroloquinoline-quinone-ethanol-dehydrogenase-in-methylobacterium-extorquens-am1-extends-lanthanide-dependent-metabolism-to-multicarbon-substrates
#8
Nathan M Good, Huong N Vu, Carly J Suriano, Gabriel A Subuyuj, Elizabeth Skovran, N Cecilia Martinez-Gomez
: Lanthanides are utilized by microbial methanol dehydrogenases, and it has been proposed that lanthanides may be important for other type I alcohol dehydrogenases. A triple mutant strain (mxaF xoxF1 xoxF2; named MDH-3), deficient in the three known methanol dehydrogenases of the model methylotroph Methylobacterium extorquens AM1, is able to grow poorly with methanol if exogenous lanthanides are added to the growth medium. When the gene encoding a putative quinoprotein ethanol dehydrogenase, exaF, was mutated in the MDH-3 background, the quadruple mutant strain could no longer grow on methanol in minimal medium with added lanthanum (La(3+))...
November 15, 2016: Journal of Bacteriology
https://www.readbyqxmd.com/read/27565673/comparative-analysis-of-l-sorbose-dehydrogenase-by-docking-strategy-for-2-keto-l-gulonic-acid-production-in-ketogulonicigenium-vulgare-and-bacillus-endophyticus-consortium
#9
Si Chen, Nan Jia, Ming-Zhu Ding, Ying-Jin Yuan
Improving the yield of 2-keto-L-gulonic acid (2-KGA), the direct precursor of vitamin C, draws more and more attention in industrial production. In this study, we try to increase the 2-KGA productivity by computer-aided selection of genes encoding L-sorbose dehydrogenases (SDH) of Ketogulonicigenium vulgare. First, six SDHs were modeled by docking strategy to predict the binding mode with co-factor PQQ. The binding energy between SSDA1-H/SSDA1-L and PQQ was the highest, followed by SSDA3/SSDA2. The binding energy between SSDA1-P/SSDB and PQQ was the lowest...
November 2016: Journal of Industrial Microbiology & Biotechnology
https://www.readbyqxmd.com/read/27526146/effects-of-antioxidant-supplements-biopqq%C3%A2-on-cerebral-blood-flow-and-oxygen-metabolism-in-the-prefrontal-cortex
#10
Masahiko Nakano, Yuta Murayama, Lizhen Hu, Kazuto Ikemoto, Tatsuo Uetake, Kaoru Sakatani
Pyrroloquinoline quinone (PQQ) is a quinone compound originally identified in methanol-utilizing bacteria and is a cofactor for redox enzymes. At the Meeting of the International Society on Oxygen Transport to Tissue (ISOTT) 2014, we reported that PQQ disodium salt (BioPQQ™) improved cognitive function in humans, as assessed by the Stroop test. However, the physiological mechanism of PQQ remains unclear. In the present study, we measured regional cerebral blood flow (rCBF) and oxygen metabolism in prefrontal cortex (PFC), before and after administration of PQQ, using time-resolved near-infrared spectroscopy (tNIRS)...
2016: Advances in Experimental Medicine and Biology
https://www.readbyqxmd.com/read/27491947/the-cooperativity-effect-in-the-reaction-of-soluble-quinoprotein-pqq-containing-glucose-dehydrogenase-is-not-due-to-subunit-interaction-but-to-substrate-assisted-catalysis
#11
Johannis A Duine, Marc J F Strampraad, Wilfred R Hagen, Simon de Vries
: Soluble quinoprotein (PQQ-containing) glucose dehydrogenase (sGDH, EC 1.1.99.35) catalyzes the oxidation of β-d-glucose to d-glucono-δ-lactone. Although sGDH has many analytical applications, the relationship between activity and substrate concentration is not well established. Previous steady-state kinetic studies revealed a negative cooperativity effect which has recently been ascribed to subunit interaction. To investigate this conclusion, stopped-flow kinetic experiments were carried out on the reaction in which oxidized enzyme (Eox ) was reduced with substrates to Ered ...
October 2016: FEBS Journal
https://www.readbyqxmd.com/read/27464830/novel-and-efficient-screening-of-pqq-high-yielding-strains-and-subsequent-cultivation-optimization
#12
Zhenjun Si, Jianzhong Zhu, Wenguang Wang, Lei Huang, Peilian Wei, Jin Cai, Zhinan Xu
A novel and efficient screening method for pyrroloquinoline quinone (PQQ) high-yielding methylotrophic strains was developed by using glucose dehydrogenase apoenzyme (GDHA) which depended on PQQ as the cofactor. Using this high-throughput method, PQQ high-yielding strains were rapidly screened out from thousands of methylotrophic colonies at a time. The comprehensive phylogenetic analysis revealed that the highest PQQ-producing strain zju323 (CCTCC M 2016079) could be assigned to a novel species in the genus Methylobacillus of the Betaproteobacteria...
July 28, 2016: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/27463000/engineered-pqq-glucose-dehydrogenase-as-a-universal-biosensor-platform
#13
Zhong Guo, Lindy Murphy, Viktor Stein, Wayne A Johnston, Siro Alcala-Perez, Kirill Alexandrov
Biosensors with direct electron output hold promise for nearly seamless integration with portable electronic devices. However, so far, they have been based on naturally occurring enzymes that significantly limit the spectrum of detectable analytes. Here, we present a novel biosensor architecture based on analyte-driven intermolecular recombination and activity reconstitution of a re-engineered component of glucometers: PQQ-glucose dehydrogenase. We demonstrate that this sensor architecture can be rapidly adopted for the detection of immunosuppressant drugs, α-amylase protein, or protease activity of thrombin and Factor Xa...
August 17, 2016: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/27338639/ph-dependent-electron-transfer-reaction-and-direct-bioelectrocatalysis-of-the-quinohemoprotein-pyranose-dehydrogenase
#14
Kouta Takeda, Hirotoshi Matsumura, Takuya Ishida, Makoto Yoshida, Kiyohiko Igarashi, Masahiro Samejima, Hiroyuki Ohno, Nobuhumi Nakamura
A pyranose dehydrogenase from Coprinopsis cinerea (CcPDH) is an extracellular quinohemoeprotein, which consists a b-type cytochrome domain, a pyrroloquinoline-quinone (PQQ) domain, and a family 1-type carbohydrate-binding module. The electron transfer reaction of CcPDH was studied using some electron acceptors and a carbon electrode at various pH levels. Phenazine methosulfate (PMS) reacted directly at the PQQ domain, whereas cytochrome c (cyt c) reacted via the cytochrome domain of intact CcPDH. Thus, electrons are transferred from reduced PQQ in the catalytic domain of CcPDH to heme b in the N-terminal cytochrome domain, which acts as a built-in mediator and transfers electron to a heterogenous electron transfer protein...
August 26, 2016: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/27242684/selection-of-the-n-acylhomoserine-lactone-degrading-bacterium-alteromonas-stellipolaris-pqq-42-and-of-its-potential-for-biocontrol-in-aquaculture
#15
Marta Torres, Esther Rubio-Portillo, Josefa Antón, Alfonso A Ramos-Esplá, Emilia Quesada, Inmaculada Llamas
The production of virulence factors by many pathogenic microorganisms depends on the intercellular communication system called quorum sensing, which involves the production and release of signal molecules known as autoinducers. Based on this, new-therapeutic strategies have emerged for the treatment of a variety of infections, such as the enzymatic degradation of signaling molecules, known as quorum quenching (QQ). In this study, we present the screening of QQ activity amongst 450 strains isolated from a bivalve hatchery in Granada (Spain), and the selection of the strain PQQ-42, which degrades a wide range of N-acylhomoserine lactones (AHLs)...
2016: Frontiers in Microbiology
https://www.readbyqxmd.com/read/27231346/crystal-structure-and-function-of-pqqf-protein-in-the-pyrroloquinoline-quinone-biosynthetic-pathway
#16
Qiaoe Wei, Tingting Ran, Chencui Ma, Jianhua He, Dongqing Xu, Weiwu Wang
Pyrroloquinoline quinone (PQQ) has received considerable attention due to its numerous important physiological functions. PqqA is a precursor peptide of PQQ with two conserved residues: glutamate and tyrosine. After linkage of the Cγ of glutamate and Cϵ of tyrosine by PqqE, these two residues are hypothesized to be cleaved from PqqA by PqqF. The linked glutamate and tyrosine residues are then used to synthesize PQQ. Here, we demonstrated that the pqqF gene is essential for PQQ biosynthesis as deletion of it eliminated the inhibition of prodigiosin production by glucose...
July 22, 2016: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/27230956/identification-of-lactate-dehydrogenase-as-a-mammalian-pyrroloquinoline-quinone-pqq-binding-protein
#17
Mitsugu Akagawa, Kenji Minematsu, Takahiro Shibata, Tatsuhiko Kondo, Takeshi Ishii, Koji Uchida
Pyrroloquinoline quinone (PQQ), a redox-active o-quinone, is an important nutrient involved in numerous physiological and biochemical processes in mammals. Despite such beneficial functions, the underlying molecular mechanisms remain to be established. In the present study, using PQQ-immobilized Sepharose beads as a probe, we examined the presence of protein(s) that are capable of binding PQQ in mouse NIH/3T3 fibroblasts and identified five cellular proteins, including l-lactate dehydrogenase (LDH) A chain, as potential mammalian PQQ-binding proteins...
2016: Scientific Reports
https://www.readbyqxmd.com/read/27209211/amelioration-of-cadmium-and-mercury-induced-liver-and-kidney-damage-in-rats-by-genetically-engineered-probiotic-escherichia-coli-nissle-1917-producing-pyrroloquinoline-quinone-with-oral-supplementation-of-citric-acid
#18
Ruma Raghuvanshi, Archana Chaudhari, G Naresh Kumar
OBJECTIVE: Antioxidants, chelating agents, and probiotics are used to manage the toxic effects of cadmium (Cd) and mercury (Hg). The aim of this study was to investigate the combined effects of antioxidants, chelating agents, and probiotics against heavy metal toxicity. METHOD: Genetically modified probiotic Escherichia coli Nissle 1917 (EcN-20) producing a potent water soluble antioxidant pyrroloquinoline quinone (PQQ) was supplemented with oral citric acid and compared with another genetically modified probiotic EcN-21 producing PQQ and citric acid against oxidative stress induced by Cd and Hg...
November 2016: Nutrition
https://www.readbyqxmd.com/read/27189063/combinatorial-metabolic-engineering-of-industrial-gluconobacter-oxydans-dsm2343-for-boosting-5-keto-d-gluconic-acid-accumulation
#19
Jianfeng Yuan, Mianbin Wu, Jianping Lin, Lirong Yang
BACKGROUND: L-(+)-tartaric acid (L-TA) is an important organic acid, which is produced from the cream of tartar or stereospecific hydrolysis of the cis-epoxysuccinate. The former method is limited by the availability of raw material and the latter is dependent on the petrochemical material. Thus, new processes for the economical preparation of L-TA from carbohydrate or renewable resource would be much more attractive. Production of 5-keto-D-gluconate (5-KGA) from glucose by Gluconobacter oxydans is the first step to produce L-TA...
2016: BMC Biotechnology
https://www.readbyqxmd.com/read/27156055/synergistic-effect-of-pyrroloquinoline-quinone-and-graphene-nano-interface-for-facile-fabrication-of-sensitive-nadh-biosensor
#20
Shanying Han, Tianyu Du, Hui Jiang, Xuemei Wang
A self-assembly composite of graphene-pyrroloquinoline quinone (PQQ) was fabricated and modified on glassy carbon electrode (GCE) for sensitive detection of nicotinamide adenine dinucleotide (NADH). Chitosan (CTS) was applied to disperse graphene to form a stable robust film on GCE. A synergistic effect between PQQ and graphene was observed during the electrocatalytic oxidation of NADH, with about 260mV reduction in the oxidation potential and 2.5-fold increase in the oxidation current compared with those on the bare GCE...
April 27, 2016: Biosensors & Bioelectronics
keyword
keyword
49431
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"