Effects of H2 and electrochemical reducing power on metabolite production by Clostridium acetobutylicum KCTC1037.

A conventional fermenter (CF), a single-cathode fermenter (SCF), and a double-cathode fermenter (DCF) were employed to evaluate and compare the effects of H2 and electrochemical reducing power on metabolite production by Clostridium acetobutylicum KCTC1037. The source of the external reducing power for CF was H2, for the SCF was electrochemically reduced neutral red-modified graphite felt electrode (NR-GF), and for the DCF was electrochemically reduced combination of NR-GF and platinum plate electrodes (NR-GF/PtP). The metabolites produced from glucose or CO2 by strain KCTC1037 cultivated in the DCF were butyrate, ethanol, and butanol, but ethanol and butanol were not produced from glucose or CO2 by strain KCTC1037 cultivated in the CF and SCF.

ReHypar: a recursive hybrid chunk partitioning method using NAND-flash memory SSD.

Due to the rapid development of flash memory, SSD is considered to be the replacement of HDD in the storage market. Although SSD retains several promising characteristics, such as high random I/O performance and nonvolatility, its high expense per capacity is the main obstacle in replacing HDD in all storage solutions. An alternative is to provide a hybrid structure where a small portion of SSD address space is combined with the much larger HDD address space.

Characterization of an antibiotic produced by Bacillus subtilis JW-1 that suppresses Ralstonia solanacearum.

Bacillus subtilis JW-1 was isolated from rhizosphere soil as a potential biocontrol agent of bacterial wilt caused by Ralstonia solanacearum. Seed treatment followed by a soil drench application with this strain resulted in >80% reduction in bacterial wilt disease compared with that in the untreated control under greenhouse conditions. The antibacterial compound produced by strain JW-1 was purified by bioactivity-guided fractionation.

Metabolic roles of carotenoid produced by non-photosynthetic bacterium Gordonia alkanivorans SKF120101.

Carotenoids produced by non-photosynthetic bacteria protect organisms against lethal photodynamic reactions and scavenge oxygenic radicals. However, the carotenoid produced by Gordonia alkanivorans SKF120101 is coupled to reducing power generation. SKF120101 selectively produces carotenoid under light conditions.

α-Glucosidase inhibitor from Buthus martensi Karsch.

A bioassay-guided fractionation of an ethanol extract of Buthus martensi Karsch led to the isolation of a potent α-glucosidase inhibitor (compound S). The structure was elucidated as a novel β-carboline glucoalkaloid, harmanyl β-d-glucopyranoside, on the basis of spectral data, including (1)H NMR, (13)C NMR, (1)H-(1)H COSY, NOESY, and HMBC. Compound S showed potent inhibitory activity against α-glucosidase, with an IC(50) value of 24 μM.

Enrichment of CO2-fixing bacteria in cylinder-type electrochemical bioreactor with built-in anode compartment.

Bacterial assimilation of CO2 into stable biomolecules using electrochemical reducing power may be an effective method to reduce atmospheric CO2 without fossil fuel combustion. For the enrichment of the CO2-fixing bacteria using electrochemical reducing power as an energy source, a cylinder-type electrochemical bioreactor with a built-in anode compartment was developed. A graphite felt cathode modified with neutral red (NR-graphite cathode) was used as a solid electron mediator to induce bacterial cells to fix CO2 using electrochemical reducing power.

Bioelectrochemical Mn(II) leaching from manganese ore by Lactococcus lactis SK071115.

L. lactis sk071115 has been shown to grow more actively and generate lower levels of lactate in glucose-defined medium with nitrate than in medium with Mn(IV). By adding Mn(IV) to a L.

Effect of glasswort (Salicornia herbacea L.) on microbial community variations in the vinegar-making process and vinegar characteristics.

Three types of nuruk were made from rice, wheat, and a rice-glasswort (6:4) mixture. Nuruk, makgeolli, and vinegar were manufactured with rice nuruk (RN), wheat nuruk (WN), and rice-glasswort nuruk (RGN). The saccharifying activity and ethanol productivity of nuruk, polyphenol content in makgeolli, and acetic acid and polyphenol content in the vinegar were increased as the result of the addition of glasswort.

Effects of electrochemical reduction reactions on the biodegradation of recalcitrant organic compounds (ROCs) and bacterial community diversity.

Five bacterial species, capable of degrading the recalcitrant organic compounds (ROCs) diethyleneglycol monomethylether (DGMME), 1-amino-2-propanol (APOL), 1-methyl-2- pyrrolidinone (NMP), diethyleneglycol monoethylether (DGMEE), tetraethyleneglycol (TEG), and tetrahydrothiophene 1,1-dioxide (sulfolane), were isolated from an enrichment culture. Cupriavidus sp. catabolized 93.

Regulation of post-translational protein arginine methylation during HeLa cell cycle.

Background: Post-translational arginine methylation which modifies protein-arginyl residues by protein arginine methyltransferase (PRMT) was investigated during synchronized HeLa cell cycle.

Methods: The lysates of cells synchronized at each stage were subjected to one and/or two dimensional electrophoresis followed by Western immunoblot using against anti-asymmetric-dimethyl-arginine (ASYM24), anti-symmetric-dimethyl-arginine (SYM10), and subclasses of PRMTs, including PRMT1, PRMT3, PRMT4 (CARM1), PRMT5, PRMT6, and PRMT7 antibodies.

Results: Proteins with approximate molecular masses of 80 kDa, 68 kDa, and 64 kDa, containing asymmetric-dimethyl-arginine (aDMA) were increased at G0/G1 to G1, which lasted until S phase.

Effect of electrochemical redox reaction on biochemical ammonium oxidation and chemical nitrite oxidation.

A modified graphite felt electrode with neutral red (NRelectrode) was shown to catalyze the chemical oxidation of nitrite to nitrate under aerobic conditions. The electrochemically oxidized NR-electrode (EO-NR-electrode) and reduced NR-electrode (ER-NR-electrode) catalyzed the oxidation of 1,094+/-39 mg/l and 382+/-45 mg/l of nitrite, respectively, for 24 h. The electrically uncharged NRelectrode (EU-NR-electrode) catalyzed the oxidation of 345+/-47 mg/l of nitrite for 24 h.

Improvement of ethanol production by electrochemical redox coupling of Zymomonas mobilis and Saccharomyces cerevisiae.

Zymomonas mobilis was immobilized in a modified graphite felt cathode with neutral red (NR-graphite cathode) and Saccharomyces cerevisiae was cultivated on a platinum plate anode to electrochemically activate ethanol fermentation. Electrochemical redox reaction was induced by 3 approximately 4 volt of electric potential charged to a cathode and an anode. Z.

Symbiotic relationship between Microbacterium sp. SK0812 and Candida tropicalis SK090404.

A bacterium growing inside yeast cytoplasm was observed by light microscope without staining. The bacterium was separately stained from yeast cell by a fluorescent dye, 4',6-diamidino-2-phenylindole (DAPI). The bacterium actively moved inside yeast cytoplasm and propagated in company with the yeast growth.

Enrichment of hydrogenotrophic methanogens in coupling with methane production using an electrochemical bioreactor.

Anaerobic digestion sludge was cultivated in an electrochemical bioreactor (ECB) to enrich the hydrogenotrophic methanogens. A modified graphite felt cathode with neutral red (NR-cathode) was charged with electrochemical reducing power generated from a solar cell. The methane and carbon dioxide collected in a Teflon bag from the ECB were more than 80 ml/l of reactant/day and less than 20 ml/l of reactant/day, respectively, whereas the methane and carbon dioxide collected from a conventional bioreactor (CB) was around 40 ml/l of reactant/day, respectively.

Effect of bacterial cell size on electricity generation in a single-compartmented microbial fuel cell.

A single-compartmented microbial fuel cell composed of a graphite felt anode modified with Neutral Red (NR-anode) and a porous Fe(II)-carbon cathode (FeC-cathode) were compared for electricity generation from Microbacterium sp. and Pseudomonas sp. under identical conditions.

Electricity generation coupled with wastewater treatment using a microbial fuel cell composed of a modified cathode with a ceramic membrane and cellulose acetate film.

A noncompartmented microbial fuel cell (NCMFC) composed of a Mn(IV)-carbon plate and a Fe(III)-carbon plate was used for electricity generation from organic wastewater without consumption of external energy. The Fe(III)-carbon plate, coated with a porous ceramic membrane and a semipermeable cellulose acetate film, was used as a cathode, which substituted for the catholyte and cathode. The Mn(IV)-carbon plate was used as an anode without a membrane or film coating.

Electrochemical activation of nitrate reduction to nitrogen by Ochrobactrum sp. G3-1 using a noncompartmented electrochemical bioreactor.

A denitrification bacterium was isolated from riverbed soil and identified as Ochrobactrum sp., whose specific enzymes for denitrification metabolism were biochemically assayed or confirmed with specific coding genes. The denitrification activity of strain G3-1 was proportional to glucose/nitrate balance, which was consistent with the theoretical balance (0.

Electrochemical and biochemical analysis of ethanol fermentation of zymomonas mobilis KCCM11336.

An electrochemical bioreactor (ECB) composed of a cathode compartment and an air anode was used in this study to characterize the ethanol fermentation of Zymomonas mobilis. The cathode and air anode were constructed of modified graphite felt with neutral red (NR) and a modified porous carbon plate with cellulose acetate and porous ceramic membrane, respectively. The air anode operates as a catalyst to generate protons and electrons from water.

Comparison between L and E gene amplification analytical methods for human papillomavirus typing.

Objective: L and E6/E7 gene amplification analyses were compared to identify human papillomavirus (HPV) infection and verify the HPV type, with the intent to minimize HPV typing errors.

Methods: L1 gene verified HPV typing was accomplished via polymerase chain reaction (PCR) and membrane assays. Verification of HPV typing via E6/E7 genes was accomplished through nested multiplexed PCR.

Isolation and physiological characterization of Bacillus clausii SKAL-16 isolated from wastewater.

An alkaliphilic bacterium, Bacillus clausii SKAL-16, was isolated from soil that had been contaminated with vegetable oil. The optimal pH and general pH range for bacterial growth was 8, and 7 to 10, respectively. The bacterium could grow on tributyrin and glycerol, but could not grow on acetate and butyrate.

Characterization of exopolysaccharide (EPS) produced by Weissella hellenica SKkimchi3 isolated from kimchi.

Weissella hellenica SKkimchi3 produces the higher exopolysaccharide (EPS) on sucrose than lactose, glucose, and fructose at pH 5 and 20 degrees C. Sucrose was exclusively used to cultivate SKkimchi3 in all experiments base on the EPS production tests. The molecular mass of EPS, as determined by gel permeation chroma-tography, was 203,000.

Production of ethanol directly from potato starch by mixed culture of Saccharomyces cerevisiae and Aspergillus niger using electrochemical bioreactor.

When cultivated aerobically, Aspergillus niger hyphae produced extracellular glucoamylase, which catalyzes the saccharification of unliquified potato starch into glucose, but not when grown under anaerobic conditions. The Km and Vmax of the extracellular glucoamylase were 652.3 mg starch l-1 and 253.

Metabolic characterization of lactic acid bacterium Lactococcus garvieae sk11, capable of reducing ferric iron, nitrate, and fumarate.

A lactic acid bacterium capable of anaerobic respiration was isolated from soil with ferric iron-containing glucose basal medium and identified as L. garvieae by using 16S rDNA sequence homology. The isolate reduced ferric iron, nitrate, and fumarate to ferrous iron, nitrite, and succinate, respectively, under anaerobic N2 atmosphere.

Effect of electrochemical redox reaction on growth and metabolism of Saccharomyces cerevisiae as an environmental factor.

The effect of an electrochemically generated oxidation-reduction potential and electric pulse on ethanol production and growth of Saccharomyces cerevisiae ATCC 26603 was experimented and compared with effects of electron mediators (neutral red, benzyl viologen, and thionine), chemical oxidants (hydrogen peroxide and hypochlorite), chemical reductants (sulfite and nitrite), oxygen, and hydrogen. The oxidation (anodic) and reduction (cathodic) potential and electric pulse activated ethanol production and growth, and changed the total soluble protein pattern of the test strain. Neutral red electrochemically reduced activated ethanol production and growth of the test strain, but benzyl viologen and thionine did not.

Oxidation of butane to butanol coupled to electrochemical redox reaction of NAD+/NADH.

A crude cell extract from a butane-utilizing bacterium, Alcaligenes sp., catalyzed the oxidation of butane to butanol coupled to NADH. A graphite electrode modified with Neutral Red (NR-electrode) catalyzed the reduction of NAD(+) to NADH.