| evolution of acetic acid bacteria during fermentation and storage of wine. | acetic acid bacteria were present at all stages of wine making, from the mature grape through vinification to conservation. a succession of gluconobacter oxydans, acetobacter pasteurianus, and acetobacter aceti during the course of these stages was noted. low levels of a. aceti remained in the wine; they exhibited rapid proliferation on short exposure of the wine to air and caused significant increases in the concentration of acetic acid. higher temperature of wine storage and higher wine ph fav ... | 1984 | 16346581 |
| acetic acid production by an electrodialysis fermentation method with a computerized control system. | in acetic acid fermentation by acetobacter aceti, the acetic acid produced inhibits the production of acetic acid by this microorganism. to alleviate this inhibitory effect, we developed an electrodialysis fermentation method such that acetic acid is continuously removed from the broth. the fermentation unit has a computerized system for the control of the ph and the concentration of ethanol in the fermentation broth. the electrodialysis fermentation system resulted in improved cell growth and h ... | 1988 | 16347520 |
| cloning of the membrane-bound aldehyde dehydrogenase gene of acetobacter polyoxogenes and improvement of acetic acid production by use of the cloned gene. | a genomic clone bank of acetobacter polyoxogenes nbi1028 constructed in escherichia coli by use of the expression vector puc18 was screened with antibody raised against membrane-bound aldehyde dehydrogenase (aldh; 75 kilodaltons [kda]) from a. polyoxogenes nbi1028. a clone that synthesized a 41-kda protein cross-reactive with anti-aldh antibody was isolated. for cloning of the full-length aldh structural gene, a cosmid gene bank was screened by southern blot hybridization with the cloned dna as ... | 1989 | 16347820 |
| putative abc transporter responsible for acetic acid resistance in acetobacter aceti. | two-dimensional gel electrophoretic analysis of the membrane fraction of acetobacter aceti revealed the presence of several proteins that were produced in response to acetic acid. a 60-kda protein, named aata, which was mostly induced by acetic acid, was prepared; aata was cloned on the basis of its nh2-terminal amino acid sequence. aata, consisting of 591 amino acids and containing atp-binding cassette (abc) sequences and abc signature sequences, belonged to the abc transporter superfamily. the ... | 2006 | 16391084 |
| acetobacter oeni sp. nov., isolated from spoiled red wine. | a bacterial strain, designated b13t, was isolated from spoiled red wine from the dão region, portugal. the strain was gram-negative, strictly aerobic, rod-shaped and motile. phylogenetic analysis on the basis of 16s rrna gene sequences indicated that b13t belonged to the genus acetobacter within the alphaproteobacteria. the closest related species was acetobacter aceti, with 98.4 % 16s rrna gene sequence similarity. dna-dna hybridization showed that b13t constituted a taxon separate from the ace ... | 2006 | 16403860 |
| biochemical and structural studies of n5-carboxyaminoimidazole ribonucleotide mutase from the acidophilic bacterium acetobacter aceti. | n5-carboxyaminoimidazole ribonucleotide (n5-cair) mutase (pure) catalyzes the reversible interconversion of acid-labile compounds n5-cair and 4-carboxy-5-aminoimidazole ribonucleotide (cair). we have examined pure from the acidophilic bacterium acetobacter aceti (aapure), focusing on its adaptation to acid ph and the roles of conserved residues his59 and his89. both aapure and escherichia coli pure showed quasi-reversible acid-mediated inactivation, but wt aapure was much more stable at ph 3.5, ... | 2006 | 16819818 |
| control of acetic acid fermentation by quorum sensing via n-acylhomoserine lactones in gluconacetobacter intermedius. | a number of gram-negative bacteria regulate gene expression in a cell density-dependent manner by quorum sensing via n-acylhomoserine lactones (ahls). gluconacetobacter intermedius nci1051, a gram-negative acetic acid bacterium, produces three different ahls, n-decanoyl-l-homoserine lactone, n-dodecanoyl-l-homoserine lactone, and an n-dodecanoyl-l-homoserine lactone with a single unsaturated bond in its acyl chain, as determined by liquid chromatography-tandem mass spectrometry. two genes encodi ... | 2008 | 18245283 |
| alanine racemase from the acidophile acetobacter aceti. | acetobacter aceti converts ethanol to acetic acid, and survives acetic acid exposure by tolerating cytoplasmic acidification. alanine racemase (alr) is a pyridoxal 5' phosphate (plp) -dependent enzyme that catalyzes the interconversion of the d- and l-isomers of alanine and has a basic ph optimum. since d-alanine is essential for peptidoglycan biosynthesis, alr must somehow function in the acidic cytoplasm of a. aceti. we report the partial purification of native a. aceti alr (aaalr) and evidenc ... | 2007 | 16843006 |
| biochemical preparation of l-ribose and l-arabinose from ribitol: a new approach. | l-ribose and l-arabinose were prepared biochemically from ribitol via a two-step reaction, by which the complete oxidation of ribitol to l-ribulose (approximately 98%) was achieved by the reaction of washed cells of acetobacter aceti ifo 3281. the produced l-ribulose was then used as a substrate for the production of l-ribose and l-arabinose. the isomerization of l-ribulose to l-ribose and l-arabinose was carried out using l-ribose isomerase (l-ri) of acinetobacter sp. strain dl-28 and l-arabino ... | 1999 | 16232643 |
| novel nitrogen-fixing acetobacter nitrogenifigens sp. nov., isolated from kombucha tea. | the four nitrogen-fixing bacteria so far described in the family acetobacteraceae belong to the genera gluconacetobacter and acetobacter. nitrogen-fixing bacterial strain rg1(t) was isolated from kombucha tea and, based on the phylogenetic analysis of 16s rrna gene sequence which is supported by a high bootstrap value, was found to belong to the genus acetobacter. strain rg1(t) differed from acetobacter aceti, the nearest member with a 16s rrna gene sequence similarity of 98.2 %, and type strain ... | 2006 | 16902028 |
| acidic extracellular proteases from microrganisms of fairly acidic niche. | the protein population secreted from three wine-contaminant microorganisms was studied by two-dimensional electrophoresis and screened for proteases. proteolytic enzymes were electrophoretically purified and their activity, optimum ph and temperature determined. the protease of acetobacter aceti maintained its activity over the range of phs 3.0-5.0, thus being of potential biotechnological interest. | 2006 | 17018019 |
| production of d-lyxose from d-glucose by microbial and enzymatic reactions. | d-arabitol was first prepared from d-glucose using candida famata r28. the reaction gave 5.0% d-arabitol from 10.0% d-glucose. d-arabitol was then almost completely converted to d-xylulose using acetobacter aceti ifo 3281. finally, d-lyxose was prepared from d-xylulose enzymatically using l-ribose isomerase from toluene-treated cells of acinetobacter sp. strain dl-28. the isomerization reaction progressed steadily and the concentration of d-xylulose increased from 1.0 to 10.0%. about 70% of d-xy ... | 1999 | 16232684 |
| necessary corrections to the approved lists of bacterial names according to rule 40d (formerly rule 46). opinion 86. | the judicial commission affirms that, according to rule 40d, formerly rule 46, of the bacteriological code, the authorship of a number of subspecies names included on the approved lists of bacterial names must be corrected. these names are acetobacter aceti subsp. aceti, acetobacter pasteurianus subsp. pasteurianus, bacteroides melaninogenicus subsp. melaninogenicus, campylobacter fetus subsp. fetus, mycobacterium chelonae subsp. chelonae, propionibacterium freudenreichii subsp. freudenreichii, ... | 2008 | 18676492 |
| purification and molecular characterization of a quinoprotein alcohol dehydrogenase from pseudogluconobacter saccharoketogenes ifo 14464. | we have cloned and verified a gene for a novel quinoprotein alcohol dehydrogenase (adh) from pseudogluconobacter saccharoketogenes ifo 14464 that has the ability to oxidize l-sorbose to 2-keto-l-gulonic acid (2-klga). the enzyme was purified from the soluble fraction of the bacterium and was estimated to be a monomeric protein with a molecular weight of 65 kda from the analyses of sds-page and gel-filtration chromatography. an open reading frame of 1824 bp for 608 amino acid residues was estimat ... | 2001 | 16233140 |
| a novel polysaccharide involved in the pellicle formation of acetobacter aceti. | acetobacter aceti ifo 3284 has been shown to have two types of strains: one forms a smooth-surfaced colony (s strain) and the other forms a rough-surfaced colony (r strain) (matsushita et al., 1992). in this study, both s and r strains were isolated and characterized. the s strain grew well in submerged culture but very poorly in static culture. in contrast, the r strain grew well in static culture by floating on the surface of the culture medium, as well as in shaking submerged culture. scannin ... | 2002 | 16233186 |
| cloning and characterization of groesl operon in acetobacter aceti. | the groesl operon of acetobacter aceti was cloned and sequenced. we observed that groes and groel of a. aceti had high amino acid sequence homologies to groes and groel of escherichia coli and bacillus subtilis. the upstream region of the groesl operon contained the heat-shock promoter, which was previously reported in alpha-purple proteobacteria, and the highly conserved inverted repeat sequence. phylogenetic analysis revealed that the a. aceti groes and groel are very closely related to those ... | 2002 | 16233284 |
| main microorganisms involved in the fermentation of ugandan ghee. | ghee is widely produced from a traditional fermented butter-like product named mashita in western uganda. however, no detailed studies have been done to identify the microorganisms involved in mashita fermentation. the aim of this study was to identify the microorganisms present at the end of mashita ripening using culture-dependent and culture-independent techniques. the most commonly identified species of lactic acid bacteria (lab) in mashita using culture-dependent techniques were lactobacill ... | 2009 | 19577815 |
| cloning and characterization of the dnakj operon in acetobacter aceti. | the dnakj operon of acetobacter aceti was cloned and sequenced. the profile of the gene configuration was similar to that of other alpha-proteobacteria. in the dnak and dnaj proteins of a. aceti, the characteristic domains/motifs reported in other organisms were well conserved. this operon was transcribed in response to a temperature shift and exposure to ethanol/acetic acid. the overexpression of this operon in a. aceti resulted in improved growth compared to the control strain at high temperat ... | 2004 | 16233640 |
| rapid identification and enumeration of saccharomyces cerevisiae cells in wine by real-time pcr. | despite the beneficial role of saccharomyces cerevisiae in the food industry for food and beverage production, it is able to cause spoilage in wines. we have developed a real-time pcr method to directly detect and quantify this yeast species in wine samples to provide winemakers with a rapid and sensitive method to detect and prevent wine spoilage. specific primers were designed for s. cerevisiae using the sequence information obtained from a cloned random amplified polymorphic dna band that dif ... | 2005 | 16269715 |
| differential real-time pcr assay for enumeration of lactic acid bacteria in wine. | oenococcus oeni is often employed to perform the malolactic fermentation in wine production, while nonoenococcal lactic acid bacteria often contribute to wine spoilage. two real-time pcr assays were developed to enumerate the total, and nonoenococcal, lactic acid bacterial populations in wine. used together, these assays can assess the spoilage risk of juice or wine from lactic acid bacteria. | 2005 | 16332898 |
| ameyamaea chiangmaiensis gen. nov., sp. nov., an acetic acid bacterium in the alpha-proteobacteria. | two isolates, ac04(t) and ac05, were isolated from the flowers of red ginger collected in chiang mai, thailand. in phylogenetic trees based on 16s rrna gene sequences, the two isolates were included within a lineage comprised of the genera acidomonas, gluconacetobacter, asaia, kozakia, swaminathania, neoasaia, granulibacter, and tanticharoenia, and they formed an independent cluster along with the type strain of tanticharoenia sakaeratensis. the calculated pair-wise sequence similarities of isol ... | 2009 | 19809199 |
| structural characterisation of unsaturated bacterial hopanoids by atmospheric pressure chemical ionisation liquid chromatography/ion trap mass spectrometry. | the production of bacteriohopanepolyols (bhps) is widespread in many different groups of prokaryotes; however, unsaturated components are less common except amongst the acetic acid bacteria. here we describe the characterisation of mono- (delta(6) or delta(11)) and diunsaturated (delta(6,11)) bacteriohopanetetrols isolated from the acetic acid bacterium gluconacetobacter xylinus (formerly acetobacter aceti ssp. xylinum) by atmospheric pressure chemical ionisation ion trap mass spectrometry (apci ... | 2007 | 17443490 |
| multiple active site histidine protonation states in acetobacter aceti n5-carboxyaminoimidazole ribonucleotide mutase detected by redor nmr. | class i pure (n5-carboxyaminoimidazole mutase) catalyzes a chemically unique mutase reaction. a working mechanistic hypothesis involves a histidine (his45 in escherichia coli pure) functioning as a general acid, but no evidence for multiple protonation states has been obtained. solution nmr is a peerless tool for this task but has had limited application to enzymes, most of which are larger than its effective molecular size limit. solid-state nmr is not subject to this limit. redor nmr studies o ... | 2007 | 17655332 |
| increased internal and external bacterial load during drosophila aging without life-span trade-off. | the role of microbial load during aging of the adult fruit fly drosophila melanogaster is incompletely understood. here we show dramatic increases in aerobic and anaerobic bacterial load during aging, both inside the body and on the surface. scanning electron microscopy and cell staining analyses of the surface of aged flies detected structures resembling abundant small bacteria and bacterial biofilms. bacteria cultured from laboratory flies included aerobic species acetobacter aceti, acetobacte ... | 2007 | 17681150 |
| analysis of proteins responsive to acetic acid in acetobacter: molecular mechanisms conferring acetic acid resistance in acetic acid bacteria. | acetic acid bacteria are used for industrial vinegar production because of their remarkable ability to oxidize ethanol and high resistance to acetic acid. although several molecular machineries responsible for acetic acid resistance in acetic acid bacteria have been reported, the entire mechanism that confers acetic acid resistance has not been completely understood. one of the promising methods to elucidate the entire mechanism is global analysis of proteins responsive to acetic acid by two-dim ... | 2008 | 17920150 |
| genera and species in acetic acid bacteria. | taxonomic studies of acetic acid bacteria were historically surveyed. the genus acetobacter was first introduced in 1898 with a single species, acetobacter aceti. the genus gluconobacter was proposed in 1935 for strains with intense oxidation of glucose to gluconic acid rather than oxidation of ethanol to acetic acid and no oxidation of acetate. the genus "acetomonas" was described in 1954 for strains with polar flagellation and no oxidation of acetate. the proposals of the two generic names wer ... | 2008 | 18199517 |
| tanticharoenia sakaeratensis gen. nov., sp. nov., a new osmotolerant acetic acid bacterium in the alpha-proteobacteria. | tanticharoenia sakaeratensis gen. nov., sp. nov. is proposed for three strains isolated from soil collected in thailand. the three strains, ac37(t), ac38, and ac39, were included within a lineage comprising the genera asaia, kozakia, swaminathania, neoasaia, acetobacter, gluconobacter, and saccharibacter in a phylogenetic tree based on 16s rrna gene sequences, but formed a quite different, independent cluster. pair-wise sequence similarities of strain ac37(t) were 96.5-92.1% to the type strains ... | 2008 | 18323667 |
| a specialized citric acid cycle requiring succinyl-coenzyme a (coa):acetate coa-transferase (aarc) confers acetic acid resistance on the acidophile acetobacter aceti. | microbes tailor macromolecules and metabolism to overcome specific environmental challenges. acetic acid bacteria perform the aerobic oxidation of ethanol to acetic acid and are generally resistant to high levels of these two membrane-permeable poisons. the citric acid cycle (cac) is linked to acetic acid resistance in acetobacter aceti by several observations, among them the oxidation of acetate to co2 by highly resistant acetic acid bacteria and the previously unexplained role of a. aceti citr ... | 2008 | 18502856 |
| immobilization of acetobacter acoti on cellulose ion exchangers: adsorption isotherms. | the adsorptive behavior of cells of acetobacter aceti, atcc 23746, on deae-, ecteola-, teae-, and dehpae-cellulose ion exchangers in a modified hoyer's medium at 30 degrees c was investigated. the maximum observed adsorption capacities varied from 46 to 64 mg dry wt/g resin. the langmuir isotherm form was used to fit the data, since the cells formed a monolayer on the resin and exhibited saturation. the equilibrium constant in the langmuir expression was qualitatively correlated with the surface ... | 1986 | 18555442 |
| immobilization of microorganisms by adhesion: interplay of electrostatic and nonelectrostatic interactions. | the adhesion of three microorganisms (saccharomyces cerevisiae, acetobacter aceti, and moniliella pollinis) to different materials has been studied using various supports (glass, metals, plastics), some of which were treated by an fe(iii) solution. the surface properties of the cells were characterized by the zeta potential and an index of hydrophobicity; characterization of the supports involved surface chemical analysis (xps) and contact angle measurements. cell suspensions in pure water at a ... | 1987 | 18581378 |
| acetic acid production using a fermentor equipped with a hollow fiber filter module. | the continuous production of acetic acid by acetobacter aceti m23 was carried out using a fermentor equipped with a hollow fiber filter module. the culture continued for 830 h with various dilution rates, which were changed stepwisely from low to high. the final cell concentration was 21.9 g dry cell/l and the maximum productivity of acetic acid was 12.7 g/l.h for the exit acetic acid concentration of about 50 g/l. the productivity was higher than any literature's values surveyed so far. the cel ... | 1989 | 18588001 |
| manufacture of a beverage from cheese whey using a "tea fungus" fermentation. | kombucha is a sour beverage reported to have potential health effects prepared from the fermentation of black tea and sugar with a "tea fungus", a symbiotic culture of acetic acid bacteria and yeasts. although black tea is the preferred substrate for kombucha fermentation, other beverages have also been tested as substrates with fair results. cheese whey is a by-product with a good amount of fermentable lactose that has been used before in the production of beverages, so the objective of this st ... | 2003 | 17061515 |
| structure of a nadh-insensitive hexameric citrate synthase that resists acid inactivation. | acetobacter aceti converts ethanol to acetic acid, and strains highly resistant to both are used to make vinegar. a. aceti survives acetic acid exposure by tolerating cytoplasmic acidification, which implies an unusual adaptation of cytoplasmic components to acidic conditions. a. aceti citrate synthase (aacs), a hexameric type ii citrate synthase, is required for acetic acid resistance and, therefore, would be expected to function at low ph. recombinant aacs has intrinsic acid stability that may ... | 2006 | 17087502 |
| real-time quantitative pcr (qpcr) and reverse transcription-qpcr for detection and enumeration of total yeasts in wine. | real-time pcr, or quantitative pcr (qpcr), has been developed to rapidly detect and quantify the total number of yeasts in wine without culturing. universal yeast primers were designed from the variable d1/d2 domains of the 26s rrna gene. these primers showed good specificity with all the wine yeasts tested, and they did not amplify the most representative wine species of acetic acid bacteria and lactic acid bacteria. numerous standard curves were constructed with different strains and species g ... | 2006 | 17088381 |
| the sphingomonas plasmid pcar3 is involved in complete mineralization of carbazole. | we determined the complete 254,797-bp nucleotide sequence of the plasmid pcar3, a carbazole-degradative plasmid from sphingomonas sp. strain ka1. a region of about 65 kb involved in replication and conjugative transfer showed similarity to a region of plasmid pnl1 isolated from the aromatic-degrading novosphingobium aromaticivorans strain f199. the presence of many insertion sequences, transposons, repeat sequences, and their remnants suggest plasticity of this plasmid in genetic structure. alth ... | 2007 | 17172338 |
| the sphingomonas plasmid pcar3 is involved in complete mineralization of carbazole. | we determined the complete 254,797-bp nucleotide sequence of the plasmid pcar3, a carbazole-degradative plasmid from sphingomonas sp. strain ka1. a region of about 65 kb involved in replication and conjugative transfer showed similarity to a region of plasmid pnl1 isolated from the aromatic-degrading novosphingobium aromaticivorans strain f199. the presence of many insertion sequences, transposons, repeat sequences, and their remnants suggest plasticity of this plasmid in genetic structure. alth ... | 2007 | 17172338 |
| atomic-resolution crystal structure of thioredoxin from the acidophilic bacterium acetobacter aceti. | the crystal structure of thioredoxin (aatrx) from the acetic acid bacterium acetobacter aceti was determined at 1 a resolution. this is currently the highest resolution crystal structure available for any thioredoxin. thioredoxins facilitate thiol-disulfide exchange, a process that is expected to be slow at the low ph values encountered in the a. aceti cytoplasm. despite the apparent need to function at low ph, neither the active site nor the surface charge distribution of aatrx is notably diffe ... | 2007 | 17192591 |
| dynamics and biodiversity of populations of lactic acid bacteria and acetic acid bacteria involved in spontaneous heap fermentation of cocoa beans in ghana. | the ghanaian cocoa bean heap fermentation process was studied through a multiphasic approach, encompassing both microbiological and metabolite target analyses. a culture-dependent (plating and incubation, followed by repetitive-sequence-based pcr analyses of picked-up colonies) and culture-independent (denaturing gradient gel electrophoresis [dgge] of 16s rrna gene amplicons, pcr-dgge) approach revealed a limited biodiversity and targeted population dynamics of both lactic acid bacteria (lab) an ... | 2007 | 17277227 |
| molecular detection of bacteria in plant tissues, using universal 16s ribosomal dna degenerated primers. | highly specific, sensitive and rapid tests are required for the detection and identification of covert bacterial contaminations in plant tissue cultures. current methods available for this purpose are tedious, time consuming, highly error prone, expensive, require advanced technical expertise and are sometimes ineffective. we report here the development of a sensitive polymerase chain reaction (pcr) based method for the rapid detection and identification of bacteria occurring in plant tissue cul ... | 2014 | 26019546 |
| n5-cair mutase: role of a co2 binding site and substrate movement in catalysis. | n5-carboxyaminoimidazole ribonucleotide mutase (n5-cair mutase or pure) from escherichia coli catalyzes the reversible interconversion of n5-cair to carboxyaminoimidazole ribonucleotide (cair) with direct co2 transfer. site-directed mutagenesis, a ph-rate profile, dft calculations, and x-ray crystallography together provide new insight into the mechanism of this unusual transformation. these studies suggest that a conserved, protonated histidine (his45) plays an essential role in catalysis. the ... | 2007 | 17298082 |
| a novel pyrroloquinoline quinone-dependent 2-keto-d-glucose dehydrogenase from pseudomonas aureofaciens. | a gene encoding an enzyme similar to a pyrroloquinoline quinone (pqq)-dependent sugar dehydrogenase from filamentous fungi, which belongs to new auxiliary activities (aa) family 12 in the cazy database, was cloned from pseudomonas aureofaciens. the deduced amino acid sequence of the cloned enzyme showed only low homology to previously characterized pqq-dependent enzymes, and multiple-sequence alignment analysis showed that the enzyme lacks one of the three conserved arginine residues that functi ... | 2015 | 25645559 |
| recombinant organisms for production of industrial products. | a revolution in industrial microbiology was sparked by the discoveries of ther double-stranded structure of dna and the development of recombinant dna technology. traditional industrial microbiology was merged with molecular biology to yield improved recombinant processes for the industrial production of primary and secondary metabolites, protein biopharmaceuticals and industrial enzymes. novel genetic techniques such as metabolic engineering, combinatorial biosynthesis and molecular breeding te ... | 2009 | 21326937 |
| recombinant organisms for production of industrial products. | a revolution in industrial microbiology was sparked by the discoveries of ther double-stranded structure of dna and the development of recombinant dna technology. traditional industrial microbiology was merged with molecular biology to yield improved recombinant processes for the industrial production of primary and secondary metabolites, protein biopharmaceuticals and industrial enzymes. novel genetic techniques such as metabolic engineering, combinatorial biosynthesis and molecular breeding te ... | 2009 | 21326937 |
| quantification of the expression of reference and alcohol dehydrogenase genes of some acetic acid bacteria in different growth conditions. | the aim of this study was to develop a reliable system to analyse the expression of the pyrroloquinoline quinone (pqq)-alcohol dehydrogenase (adh) and test its ability to predict the growth and oxidative activity of some acetic acid bacteria (aab). | 2009 | 19200331 |
| succession of selected strains of acetobacter pasteurianus and other acetic acid bacteria in traditional balsamic vinegar. | the application of a selected acetobacter pasteurianus strain for traditional balsamic vinegar production was assessed. genomic dna was extracted from biofilms after enrichment cultures on gyc medium (10% glucose, 1.0% yeast extract, 2.0% calcium carbonate) and used for pcr/denaturing gradient gel electrophoresis, 16s rrna gene sequencing, and enterobacterial repetitive intergenic consensus/pcr sequencing. results suggested that double-culture fermentation is suitable for traditional balsamic vi ... | 2009 | 19251897 |
| in vivo and in vitro evaluation of an acetobacter xylinum synthesized microbial cellulose membrane intended for guided tissue repair. | barrier materials as cellulose membranes are used for guided tissue repair. however, it is essential that the surrounding tissues accept the device. the present study histologically evaluated tissue reaction to a microbial cellulose membrane after subcutaneous implantation in mice. furthermore, the interaction between mesenchymal stem cells and the biomaterial was studied in vitro to evaluate its ability to act as cellular scaffold for tissue engineering. | 2009 | 19317903 |
| whole-genome analyses reveal genetic instability of acetobacter pasteurianus. | acetobacter species have been used for brewing traditional vinegar and are known to have genetic instability. to clarify the mutability, acetobacter pasteurianus nbrc 3283, which forms a multi-phenotype cell complex, was subjected to genome dna sequencing. the genome analysis revealed that there are more than 280 transposons and five genes with hyper-mutable tandem repeats as common features in the genome consisting of a 2.9-mb chromosome and six plasmids. there were three single nucleotide muta ... | 2009 | 19638423 |
| effects of aromatic compounds on the production of bacterial nanocellulose by gluconacetobacter xylinus. | bacterial cellulose (bc) is a polymeric nanostructured fibrillar network produced by certain microorganisms, principally gluconacetobacter xylinus. bc has a great potential of application in many fields. lignocellulosic biomass has been investigated as a cost-effective feedstock for bc production through pretreatment and hydrolysis. it is well known that detoxification of lignocellulosic hydrolysates may be required to achieve efficient production of bc. recent results suggest that phenolic comp ... | 2014 | 24884902 |
| the partial substrate dethiaacetyl-coenzyme a mimics all critical carbon acid reactions in the condensation half-reaction catalyzed by thermoplasma acidophilum citrate synthase. | citrate synthase (cs) performs two half-reactions: the mechanistically intriguing condensation of acetyl-coa with oxaloacetate (oaa) to form citryl-coa and the subsequent, slower hydrolysis of citryl-coa that generally dominates steady-state kinetics. the condensation reaction requires the abstraction of a proton from the methyl carbon of acetyl-coa to generate a reactive enolate intermediate. the carbanion of that intermediate then attacks the oaa carbonyl to furnish citryl-coa, the initial pro ... | 2009 | 19645419 |
| complete genome sequence of the sugarcane nitrogen-fixing endophyte gluconacetobacter diazotrophicus pal5. | gluconacetobacter diazotrophicus pal5 is an endophytic diazotrophic bacterium that lives in association with sugarcane plants. it has important biotechnological features such as nitrogen fixation, plant growth promotion, sugar metabolism pathways, secretion of organic acids, synthesis of auxin and the occurrence of bacteriocins. | 2009 | 19775431 |
| bioelectrocatalysis of acetobacter aceti and gluconobacter roseus for current generation. | acetobacter aceti and gluconobacter roseus, which are known to be responsible for the spoilage of wine, are used for current generation in batch-type microbial biofuel cells and it has been shown for the first time that these two microorganisms do not require mediators for the transfer of electrons to the anode. three biofuel cells were constructed with two cells containing the pure cultures of each of the microorganisms as the biocatalyst (a-mfc, g-mfc) and the third cell was constructed with t ... | 2009 | 20028071 |
| the gpsx gene encoding a glycosyltransferase is important for polysaccharide production and required for full virulence in xanthomonas citri subsp. citri. | the gram-negative bacterium xanthomonas citri subsp. citri (xac) causes citrus canker, one of the most destructive diseases of citrus worldwide. in our previous work, a transposon mutant of xac strain 306 with an insertion in the xac3110 locus was isolated in a screening that aimed at identifying genes related to biofilm formation. the xac3110 locus was named as bdp24 for biofilm-defective phenotype and the mutant was observed to be affected in extracellular polysaccharide (eps) and lipopolysacc ... | 2012 | 22404966 |
| sbng, a citrate synthase in staphylococcus aureus: a new fold on an old enzyme. | in response to iron deprivation, staphylococcus aureus produces staphyloferrin b, a citrate-containing siderophore that delivers iron back to the cell. this bacterium also possesses a second citrate synthase, sbng, that is necessary for supplying citrate to the staphyloferrin b biosynthetic pathway. we present the structure of sbng bound to the inhibitor calcium and an active site variant in complex with oxaloacetate. the overall fold of sbng is structurally distinct from tca cycle citrate synth ... | 2014 | 25336653 |
| identification and quantification of acetic acid bacteria in wine and vinegar by taqman-mgb probes. | a real-time pcr (rt-pcr) assay was developed using taqman minor groove binder (mgb) probes for the specific detection and quantification of five acetic acid bacteria (aab) species (acetobacter pasteurianus, acetobacter aceti, gluconacetobacter hansenii, gluconacetobacter europaeus and gluconobacter oxydans) in wine and vinegar. the primers and probes, designed from the 16s rrna gene, showed good specificity with the target aab species. the technique was tested on aab grown in glucose medium (gy) ... | 2010 | 20141944 |
| microbiota analysis of caspian sea yogurt, a ropy fermented milk circulated in japan. | we analyzed the microbiota of domestic ropy fermented milk, caspian sea yogurt (or 'kasupikai yohguruto' in japanese), circulated in japan. we collected six varieties from five localities. lactococcus (l) lactis ssp. cremoris was isolated from all samples as the dominant strain at levels of 10(8)-10(9) cfu/g. we show this strain produces an extracellular polysaccharide (eps) that causes the unique characteristic viscosity of the product. from analysis of the rapd pattern of 60 bacterial isolates ... | 2009 | 20163589 |
| transcriptomic and phenotypic responses of listeria monocytogenes strains possessing different growth efficiencies under acidic conditions. | in an experiment delineating aciduric strains, food and clinical listeria monocytogenes isolates tended to produce the most biomass whereas ovine and avian strains produced comparatively less biomass when exposed to high levels of sodium diacetate (sd) and potassium sorbate. compared to reference strains that exhibited greater acid sensitivity, representative food isolates with comparatively good growth capacities in the presence of 21 mm sd at ph 5.0 accumulated reduced levels of acetate anion ... | 2010 | 20511423 |
| a 28-day oral toxicity study of fermentation-derived cellulose, produced by acetobacter aceti subspecies xylinum, in f344 rats. | this study was designed to evaluate any adverse effect of fermentation-derived cellulose, produced by acetobacter aceti subspecies xylinum, when administered to both sexes of f344 rats at dietary levels of 0, 1.25, 2.5, and 5.0% for 28 days. the treatment had no adverse effects on clinical signs, mortality, body weights and food and water consumption, or on urinalysis, ophthalmology, hematology, blood biochemistry, and histopathology findings. at necropsy, slight increased absolute and relative ... | 2010 | 20519840 |
| isolation and identification of persistent chlorinated organophosphorus flame retardant-degrading bacteria. | tris(2-chloroethyl) and tris(1,3-dichloro-2-propyl) phosphates are chlorinated persistent flame retardants that have recently emerged as environmental pollutants. two bacterial strains that can degrade the compounds when they are the sole phosphorus sources have been isolated and identified as members of the sphingomonads. the strains can be useful for the bioremediation of environments contaminated with these compounds. | 2010 | 20525857 |
| molecular and catalytic properties of the aldehyde dehydrogenase of gluconacetobacter diazotrophicus, a quinoheme protein containing pyrroloquinoline quinone, cytochrome b, and cytochrome c. | several aldehyde dehydrogenase (aldh) complexes have been purified from the membranes of acetic acid bacteria. the enzyme structures and the chemical nature of the prosthetic groups associated with these enzymes remain a matter of debate. we report here on the molecular and catalytic properties of the membrane-bound aldh complex of the diazotrophic bacterium gluconacetobacter diazotrophicus. the purified aldh complex is a heterodimer comprising two subunits of 79.7 and 50 kda, respectively. reve ... | 2010 | 20802042 |
| development of a sequence-characterized amplified region marker-targeted quantitative pcr assay for strain-specific detection of oenococcus oeni during wine malolactic fermentation. | control over malolactic fermentation (mlf) is a difficult goal in winemaking and needs rapid methods to monitor oenococcus oeni malolactic starters (mls) in a stressful environment such as wine. in this study, we describe a novel quantitative pcr (qpcr) assay enabling the detection of an o. oeni strain during mlf without culturing. o. oeni strain lb221 was used as a model to develop a strain-specific sequence-characterized amplified region (scar) marker derived from a discriminatory opa20-based ... | 2010 | 20935116 |
| differential growth responses of soil bacterial taxa to carbon substrates of varying chemical recalcitrance. | soils are immensely diverse microbial habitats with thousands of co-existing bacterial, archaeal, and fungal species. across broad spatial scales, factors such as ph and soil moisture appear to determine the diversity and structure of soil bacterial communities. within any one site however, bacterial taxon diversity is high and factors maintaining this diversity are poorly resolved. candidate factors include organic substrate availability and chemical recalcitrance, and given that they appear to ... | 2011 | 21833332 |
| transcriptome response to different carbon sources in acetobacter aceti. | the draft genome sequence of acetobacter aceti nbrc 14818 was determined by whole-genome shotgun sequencing and the transcriptome profile in cells exponentially grown on ethanol, acetate or glucose was analysed by using a dna microarray. the genes for all enzymes that constitute the complete tricarboxylic acid (tca) cycle and glyoxylate pathway were identified in the genome. the tca cycle genes showed higher expression levels in a. aceti cells grown on acetate or glucose and the glyoxylate pathw ... | 2010 | 21081762 |
| neokomagataea gen. nov., with descriptions of neokomagataea thailandica sp. nov. and neokomagataea tanensis sp. nov., osmotolerant acetic acid bacteria of the +¦-proteobacteria. | isolates ah11(t) and ah13(t) were isolated from flowers of lantana and candle bush respectively collected in thailand. in phylogenetic trees based on 16s rrna gene sequences, the two isolates formed an independent cluster, which was then connected to the type strain of saccharibacter floricola. the calculated pair-wise 16s rrna gene sequence similarities of isolate ah11(t) were 95.7-92.3% to the type strains of the type species of the 12 genera of acetic acid bacteria. the dna base composition w ... | 2011 | 21389630 |
| the transcriptional response of listeria monocytogenes during adaptation to growth on lactate and diacetate includes synergistic changes that increase fermentative acetoin production. | the organic acids lactate and diacetate are commonly used in combination in ready-to-eat foods because they show synergistic ability to inhibit the growth of listeria monocytogenes. full-genome microarrays were used to investigate the synergistic transcriptomic responses of two l. monocytogenes strains, h7858 (serotype 4b) and f6854 (serotype 1/2a), to these two organic acids under conditions representing osmotic and cold stress encountered in foods. strains were exposed to brain heart infusion ... | 2011 | 21666015 |
| Changes in the gene expression profile of Acetobacter aceti during growth on ethanol. | Acetobacter aceti NBRC 14818 shows a diauxic growth profile and temporarily accumulates acetate when grown in medium containing ethanol. However, the mechanisms underlying the metabolic switching between the incomplete oxidation of ethanol and overoxidation of acetate, and the control of stress resistance systems in A. aceti cells grown on ethanol are not fully understood. In this study, time-dependent transcriptome changes in cells during growth on ethanol were analyzed by DNA microarray. In A. ... | 2011 | 22153844 |
| optimization of culture conditions to produce high yields of active acetobacter sp. cctcc m209061 cells for anti-prelog reduction of prochiral ketones. | chiral alcohols are widely used in the synthesis of chiral pharmaceuticals, flavors and functional materials and appropriate whole-cell biocatalysts offer a highly enantioselective, minimally polluting route to these valuable compounds. the recently isolated strain acetobacter sp. cctcc m209061 showed exclusive anti-prelog stereoselectivity for the reduction of prochiral ketones, but the low biomass has limited its commercialization and industrial applications. to tackle this problem, the effect ... | 2011 | 22099947 |
| Simultaneous degradation of bad wine and electricity generation with the aid of the coexisting biocatalysts Acetobacter aceti and Gluconobacter roseus. | This study describes the cooperative effect of the two biocatalysts Acetobacter aceti and Gluconobacter roseus for biodegradation as well as current generation. The electro activity of the biofilms of these two microorganisms was investigated by the bioelectrocatalytic oxidation of ethanol and glucose using cyclic voltammetry. Two chamber microbial fuel cells (MFCs) were constructed using single culture of A. aceti (A-MFC), and G. roseus (G-MFC) and also using mixed culture (AG-MFC). Each MFC wa ... | 2012 | 22130075 |
| formyl-coenzyme a (coa):oxalate coa-transferase from the acidophile acetobacter aceti has a distinctive electrostatic surface and inherent acid stability. | bacterial formyl-coa:oxalate coa-transferase (fcoct) and oxalyl-coa decarboxylase work in tandem to perform a proton-consuming decarboxylation that has been suggested to have a role in generalized acid resistance. fcoct is the product of uctb in the acidophilic acetic acid bacterium acetobacter aceti. as expected for an acid-resistance factor, uctb remains folded at the low ph values encountered in the a. aceti cytoplasm. a comparison of crystal structures of fcocts and related proteins revealed ... | 2012 | 22374910 |
| Comparative analyses of transport proteins encoded within the genomes of Mycobacterium tuberculosis and Mycobacterium leprae. | The co-emergence of multidrug resistant pathogenic bacterial strains and the HIV pandemic has made tuberculosis a leading public health threat. The causative agent is Mycobacterium tuberculosis (Mtu), a facultative intracellular parasite. Mycobacterium leprae (Mle), a related organism that causes leprosy, is an obligate intracellular parasite. Given that different transporters are required for bacterial growth and persistence under a variety of growth conditions, we conducted comparative analyse ... | 2011 | 22179038 |
| structure of succinyl-coa:3-ketoacid coa transferase from drosophila melanogaster. | succinyl-coa:3-ketoacid coa transferase (scot) plays a crucial role in ketone-body metabolism. scot from drosophila melanogaster (dmscot) was purified and crystallized. the crystal structure of dmscot was determined at 2.64 å resolution and belonged to space group p212121, with unit-cell parameters a=76.638, b=101.921, c=122.457 å, α=β=γ=90°. sequence alignment and structural analysis identified dmscot as a class i coa transferase. compared with acetobacter aceti succinyl-coa:acetate coa transfe ... | 2013 | 24100554 |
| complete genome sequence and comparative analysis of acetobacter pasteurianus 386b, a strain well-adapted to the cocoa bean fermentation ecosystem. | acetobacter pasteurianus 386b, an acetic acid bacterium originating from a spontaneous cocoa bean heap fermentation, proved to be an ideal functional starter culture for coca bean fermentations. it is able to dominate the fermentation process, thereby resisting high acetic acid concentrations and temperatures. however, the molecular mechanisms underlying its metabolic capabilities and niche adaptations are unknown. in this study, whole-genome sequencing and comparative genome analysis was used t ... | 2013 | 23902333 |
| tuning of thioredoxin redox properties by intramolecular hydrogen bonds. | thioredoxin-like proteins contain a characteristic c-x-x-c active site motif and are involved in a large number of biological processes ranging from electron transfer, cellular redox level maintenance, and regulation of cellular processes. the mechanism for deprotonation of the buried c-terminal active site cysteine in thioredoxin, necessary for dissociation of the mixed-disulfide intermediate that occurs under thiol/disulfide mediated electron transfer, is not well understood for all thioredoxi ... | 2013 | 23936007 |
| Comparative analyses of transport proteins encoded within the genomes of Mycobacterium tuberculosis and Mycobacterium leprae. | The co-emergence of multidrug resistant pathogenic bacterial strains and the HIV pandemic has made tuberculosis a leading public health threat. The causative agent is Mycobacterium tuberculosis (Mtu), a facultative intracellular parasite. Mycobacterium leprae (Mle), a related organism that causes leprosy, is an obligate intracellular parasite. Given that different transporters are required for bacterial growth and persistence under a variety of growth conditions, we conducted comparative analyse ... | 2011 | 22179038 |
| evolution of mitochondria reconstructed from the energy metabolism of living bacteria. | the ancestors of mitochondria, or proto-mitochondria, played a crucial role in the evolution of eukaryotic cells and derived from symbiotic α-proteobacteria which merged with other microorganisms - the basis of the widely accepted endosymbiotic theory. however, the identity and relatives of proto-mitochondria remain elusive. here we show that methylotrophic α-proteobacteria could be the closest living models for mitochondrial ancestors. we reached this conclusion after reconstructing the possibl ... | 2014 | 24804722 |
| review: diversity of microorganisms in global fermented foods and beverages. | culturalable and non-culturable microorganisms naturally ferment majority of global fermented foods and beverages. traditional food fermentation represents an extremely valuable cultural heritage in most regions, and harbors a huge genetic potential of valuable but hitherto undiscovered strains. holistic approaches for identification and complete profiling of both culturalable and non-culturable microorganisms in global fermented foods are of interest to food microbiologists. the application of ... | 2016 | 27047484 |
| phylum- and class-specific pcr primers for general microbial community analysis. | amplification of a particular dna fragment from a mixture of organisms by pcr is a common first step in methods of examining microbial community structure. the use of group-specific primers in community dna profiling applications can provide enhanced sensitivity and phylogenetic detail compared to domain-specific primers. other uses for group-specific primers include quantitative pcr and library screening. the purpose of the present study was to develop several primer sets targeting commonly occ ... | 2005 | 16204538 |
| contribution to the prediction of the fold code: application to immunoglobulin and flavodoxin cases. | folding nucleus of globular proteins formation starts by the mutual interaction of a group of hydrophobic amino acids whose close contacts allow subsequent formation and stability of the 3d structure. these early steps can be predicted by simulation of the folding process through a monte carlo (mc) coarse grain model in a discrete space. we previously defined mirs (most interacting residues), as the set of residues presenting a large number of non-covalent neighbour interactions during such simu ... | 2015 | 25915049 |
| biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates. | this article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." as a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gl(-1) can be achieved. the reactor ... | 2005 | 16122390 |
| enzyme structure captures four cysteines aligned for disulfide relay. | thioredoxin superfamily proteins introduce disulfide bonds into substrates, catalyze the removal of disulfides, and operate in electron relays. these functions rely on one or more dithiol/disulfide exchange reactions. the flavoenzyme quiescin sulfhydryl oxidase (qsox), a catalyst of disulfide bond formation with an interdomain electron transfer step in its catalytic cycle, provides a unique opportunity for exploring the structural environment of enzymatic dithiol/disulfide exchange. wild-type ra ... | 2014 | 24888638 |
| metabolic regulation and overproduction of primary metabolites. | overproduction of microbial metabolites is related to developmental phases of microorganisms. inducers, effectors, inhibitors and various signal molecules play a role in different types of overproduction. biosynthesis of enzymes catalysing metabolic reactions in microbial cells is controlled by well-known positive and negative mechanisms, e.g. induction, nutritional regulation (carbon or nitrogen source regulation), feedback regulation, etc. the microbial production of primary metabolites contri ... | 2008 | 21261849 |
| structure and functional characterization of pyruvate decarboxylase from gluconacetobacter diazotrophicus. | bacterial pyruvate decarboxylases (pdc) are rare. their role in ethanol production and in bacterially mediated ethanologenic processes has, however, ensured a continued and growing interest. pdcs from zymomonas mobilis (zmpdc), zymobacter palmae (zppdc) and sarcina ventriculi (svpdc) have been characterized and zmpdc has been produced successfully in a range of heterologous hosts. pdcs from the acetobacteraceae and their role in metabolism have not been characterized to the same extent. examples ... | 2014 | 25369873 |
| draft genome sequence of gluconobacter thailandicus nbrc 3257. | gluconobacter thailandicus strain nbrc 3257, isolated from downy cherry (prunus tomentosa), is a strict aerobic rod-shaped gram-negative bacterium. here, we report the features of this organism, together with the draft genome sequence and annotation. the draft genome sequence is composed of 107 contigs for 3,446,046 bp with 56.17% g+c content and contains 3,360 protein-coding genes and 54 rna genes. | 2014 | 25197448 |
| effects of kombucha on oxidative stress induced nephrotoxicity in rats. | trichloroethylene (tce) may induce oxidative stress which generates free radicals and alters antioxidants or oxygen-free radical scavenging enzymes. | 2009 | 19943946 |
| valorization of date palm (phoenix dactylifera) fruit processing by-products and wastes using bioprocess technology - review. | the date palm phoenix dactylifera has played an important role in the day-to-day life of the people for the last 7000 years. today worldwide production, utilization and industrialization of dates are continuously increasing since date fruits have earned great importance in human nutrition owing to their rich content of essential nutrients. tons of date palm fruit wastes are discarded daily by the date processing industries leading to environmental problems. wastes such as date pits represent an ... | 2013 | 23961227 |
| chronic administration of the probiotic kefir improves the endothelial function in spontaneously hypertensive rats. | the beverage obtained by fermentation of milk with kefir grains, a complex matrix containing acid bacteria and yeasts, has been shown to have beneficial effects in various diseases. however, its effects on hypertension and endothelial dysfunction are not yet clear. in this study, we evaluated the effects of kefir on endothelial cells and vascular responsiveness in spontaneously hypertensive rats (shr). | 2015 | 26715471 |
| physiological and biochemical responses of yarrowia lipolytica to dehydration induced by air-drying and freezing. | organisms that can withstand anhydrobiosis possess the unique ability to temporarily and reversibly suspend their metabolism for the periods when they live in a dehydrated state. however, the mechanisms underlying the cell's ability to tolerate dehydration are far from being fully understood. the objective of this study was to highlight, for the first time, the cellular damage to yarrowia lipolytica as a result of dehydration induced by drying/rehydration and freezing/thawing. cellular response ... | 2014 | 25350121 |
| function and x-ray crystal structure of escherichia coli yfde. | many food plants accumulate oxalate, which humans absorb but do not metabolize, leading to the formation of urinary stones. the commensal bacterium oxalobacter formigenes consumes oxalate by converting it to oxalyl-coa, which is decarboxylated by oxalyl-coa decarboxylase (oxc). oxc and the class iii coa-transferase formyl-coa:oxalate coa-transferase (fcoct) are widespread among bacteria, including many that have no apparent ability to degrade or to resist external oxalate. the evga acid response ... | 2013 | 23935849 |
| milk kefir: composition, microbial cultures, biological activities, and related products. | in recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. in this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. there are numerous commercially available kefir based-products. kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. also, the presence of kefir' ... | 2015 | 26579086 |
| parallel-up structure evidences the molecular directionality during biosynthesis of bacterial cellulose. | the "parallel-up" packing in cellulose ialpha and ibeta unit cells was experimentally demonstrated by a combination of direct-staining the reducing ends of cellulose chains and microdiffraction-tilting electron crystallographic analysis. microdiffraction investigation of nascent bacterial cellulose microfibrils showed that the reducing end of the growing cellulose chains points away from the bacterium, and this provides direct evidence that polymerization by the cellulose synthase takes place at ... | 1997 | 9256440 |
| structural biology of the purine biosynthetic pathway. | purine biosynthesis requires ten enzymatic transformations to generate inosine monophosphate. purf, purd, purl, purm, purc, and purb are common to all pathways, while purn or purt, purk/pure-i or pure-ii, purh or purp, and purj or puro catalyze the same steps in different organisms. x-ray crystal structures are available for all 15 purine biosynthetic enzymes, including 7 atp-dependent enzymes, 2 amidotransferases and 2 tetrahydrofolate-dependent enzymes. here we summarize the structures of the ... | 2008 | 18712276 |
| production of tea vinegar by batch and semicontinuous fermentation. | the fermented tea vinegar combines the beneficial properties of tea and vinegar. the complete fermentation takes 4 to 5 weeks in a batch culture and thus can be shortened by semi continuous/ continuous fermentation using immobilized bacterial cells. in the present study, alcoholic fermentation of 1.0 and 1.5% tea infusions using saccharomyces cerevisae g was carried out that resulted in 84.3 and 84.8% fermentation efficiency (fe) respectively. the batch vinegar fermentation of these wines with a ... | 2010 | 23572817 |
| production of tea vinegar by batch and semicontinuous fermentation. | the fermented tea vinegar combines the beneficial properties of tea and vinegar. the complete fermentation takes 4 to 5 weeks in a batch culture and thus can be shortened by semi continuous/ continuous fermentation using immobilized bacterial cells. in the present study, alcoholic fermentation of 1.0 and 1.5% tea infusions using saccharomyces cerevisae g was carried out that resulted in 84.3 and 84.8% fermentation efficiency (fe) respectively. the batch vinegar fermentation of these wines with a ... | 2010 | 23572817 |
| single-molecule paleoenzymology probes the chemistry of resurrected enzymes. | it is possible to travel back in time at the molecular level by reconstructing proteins from extinct organisms. here we report the reconstruction, based on sequence predicted by phylogenetic analysis, of seven precambrian thioredoxin enzymes (trx) dating back between ~1.4 and ~4 billion years (gyr). the reconstructed enzymes are up to 32 °c more stable than modern enzymes, and the oldest show markedly higher activity than extant ones at ph 5. we probed the mechanisms of reduction of these enzyme ... | 2011 | 21460845 |
| in silico classification of proteins from acidic and neutral cytoplasms. | protein acidostability is a common problem in biopharmaceutical and other industries. however, it remains a great challenge to engineer proteins for enhanced acidostability because our knowledge of protein acidostabilization is still very limited. in this paper, we present a comparative study of proteins from bacteria with acidic (ap) and neutral cytoplasms (np) using an integrated statistical and machine learning approach. we construct a set of 393 non-redundant ap-np ortholog pairs and calcula ... | 2012 | 23049817 |
| expression of human paraoxonase 1 decreases superoxide levels and alters bacterial colonization in the gut of drosophila melanogaster. | paraoxonases (pon) are a family of proteins (pon1, 2 and 3) with multiple enzymatic activities. pon1 interferes with homoserine lactone-mediated quorum sensing in bacteria and with reactive oxygen species (ros) in humans and mice. pon1 gene mutations have been linked to multiple traits, including aging, and diseases of the cardiovascular, nervous and gastrointestinal system. the overlapping enzymatic activities in the pon family members and high linkage disequilibrium rates within their polymorp ... | 2012 | 22952763 |
| gut-associated microbes of drosophila melanogaster. | there is growing interest in using drosophila melanogaster to elucidate mechanisms that underlie the complex relationships between a host and its microbiota. in addition to the many genetic resources and tools drosophila provides, its associated microbiota is relatively simple (1-30 taxa), in contrast to the complex diversity associated with vertebrates (> 500 taxa). these attributes highlight the potential of this system to dissect the complex cellular and molecular interactions that occur betw ... | 2012 | 22572876 |
| contribution of coa ligases to benzenoid biosynthesis in petunia flowers. | biosynthesis of benzoic acid from phe requires shortening of the side chain by two carbons, which can occur via the β-oxidative or nonoxidative pathways. the first step in the β-oxidative pathway is cinnamoyl-coa formation, likely catalyzed by a member of the 4-coumarate:coa ligase (4cl) family that converts a range of trans-cinnamic acid derivatives into the corresponding coa thioesters. using a functional genomics approach, we identified two potential coa-ligases from petunia (petunia hybrida) ... | 2012 | 22649270 |
| the future of butyric acid in industry. | in this paper, the different applications of butyric acid and its current and future production status are highlighted, with a particular emphasis on the biofuels industry. as such, this paper discusses different issues regarding butyric acid fermentations and provides suggestions for future improvements and their approaches. | 2012 | 22593687 |
| primordial soup or vinaigrette: did the rna world evolve at acidic ph? | the rna world concept has wide, though certainly not unanimous, support within the origin-of-life scientific community. one view is that life may have emerged as early as the hadean eon 4.3-3.8 billion years ago with an atmosphere of high co(2) producing an acidic ocean of the order of ph 3.5-6. compatible with this scenario is the intriguing proposal that life arose within alkaline (ph 9-11) deep-sea hydrothermal vents like those of the 'lost city', with the interface with the acidic ocean crea ... | 2012 | 22264281 |
| effects of kefir on the cardiac autonomic tones and baroreflex sensitivity in spontaneously hypertensive rats. | it has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (shr). in the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (hr) and baroreflex sensitivity (brs) in shr was evaluated. | 2016 | 27375490 |