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the microbiology of ghanaian cocoa fermentations analysed using culture-dependent and culture-independent methods.export of cocoa beans is of great economic importance in ghana and several other tropical countries. raw cocoa has an astringent unpleasant taste and a spontaneous fermentation is the first step in a process leading to cocoa beans with the characteristic cocoa flavour and taste. the microbiology of ghanaian cocoa fermentations was investigated using culture-dependent and culture-independent methods. samples were collected at 12 hour intervals during 96-144 hour tray and traditional heap fermenta ...200717161485
native microbial colonization of drosophila melanogaster and its use as a model of enterococcus faecalis pathogenesis.enterococci are commensal organisms of the gastrointestinal (gi) tracts of a broad range of mammalian and insect hosts, but they are also leading causes of nosocomial infection. little is known about the ecological role of enterococci in the gi tract consortia. to develop a tractable model for studying the roles of these organisms as commensals and pathogens, we characterized the drosophila melanogaster microflora and examined the occurrence of enterococci in the gastrointestinal consortium of d ...200717220307
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 ...200717277227
helicobacter pylori estv: identification, cloning, and characterization of the first lipase isolated from an epsilon-proteobacterium.bacterial lipases are attracting an enormous amount of attention due to their wide biotechnological applications and due to their roles as virulence factors in some bacteria. helicobacter pylori is a significant and widespread pathogen which produces a lipase(s) and phospholipases that seem to play a role in mucus degradation and the release of proinflammatory and cytotoxic compounds. however, no h. pylori lipase(s) has been isolated and described previously. therefore, a search for putative lip ...200717293528
complete genome sequence of the prototype lactic acid bacterium lactococcus lactis subsp. cremoris mg1363.lactococcus lactis is of great importance for the nutrition of hundreds of millions of people worldwide. this paper describes the genome sequence of lactococcus lactis subsp. cremoris mg1363, the lactococcal strain most intensively studied throughout the world. the 2,529,478-bp genome contains 81 pseudogenes and encodes 2,436 proteins. of the 530 unique proteins, 47 belong to the cog (clusters of orthologous groups) functional category "carbohydrate metabolism and transport," by far the largest ...200717307855
microbial asymmetric oxidation of 2-butyl-1,3-propanediol.microbial asymmetric oxidation of 2-butyl-1,3-propanediol was investigated for an efficient synthesis of s- and r-enantiomers of 2-hydroxymethylhexanoic acid (2-hmha). from an intensive survey of the stocked bacterial strains, acetobacter pasteurianus iam 12073 and pseudomonas putida ifo 3738 were found to show the highest s- and r-2-hmha-producing activity, respectively. under optimized conditions, a. pasteurianus (351 mg dry cell weight) and p. putida (642 mg dry cell weight) cells produced 12 ...200717453192
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 ...200717681150
influence of turning and environmental contamination on the dynamics of populations of lactic acid and acetic acid bacteria involved in spontaneous cocoa bean heap fermentation in ghana.the influence of turning and environmental contamination on six spontaneous cocoa bean heap fermentations performed in ghana was studied through a multiphasic approach, encompassing both microbiological (culture-dependent and culture-independent techniques) and metabolite target analyses. a sensory analysis of chocolate made from the fermented, dried beans was performed as well. only four clusters were found among the isolates of acetic acid bacteria (aab) identified: acetobacter pasteurianus, a ...200817993565
transposable modules generated by a single copy of insertion sequence ispme1 and their influence on structure and evolution of natural plasmids of paracoccus methylutens dm12.we demonstrated that a single copy of insertion sequence ispme1 can mobilize adjacent segments of genomic dna of paracoccus methylutens dm12, which leads to the generation of diverse transposable elements of various size and dna contents. all elements (named transposable modules [tmos]) contain ispme1 (placed at the 5' ends of the elements) and have variable 3'-end regions of between 0.5 and 5 kb. ispme1 was shown to encode an outwardly oriented promoter, which may activate the transcription of ...200818296518
application of culture culture-independent molecular biology based methods to evaluate acetic acid bacteria diversity during vinegar processing.acetic acid bacteria (aab) are considered fastidious microorganisms because they are difficult to isolate and cultivate. different molecular approaches were taken to detect aab diversity, independently of their capacity to grow in culture media. those methods were tested in samples that originated during traditional vinegar production. bacterial diversity was assessed by analysis of 16s rrna gene, obtained by pcr amplifications of dna extracted directly from the acetification container. bacteria ...200818571262
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, ...200818676492
hydrogen peroxide resistance of acetobacter pasteurianus nbrc3283 and its relationship to acetic acid fermentation.the bacterium acetobacter pasteurianus can ferment acetic acid, a process that proceeds at the risk of oxidative stress. to understand the stress response, we investigated catalase and oxyr in a. pasteurianus nbrc3283. this strain expresses only a kate homolog as catalase, which is monofunctional and growth dependent. disruption of the oxyr gene increased kate activity, but both the kate and oxyr mutant strains showed greater sensitivity to hydrogen peroxide as compared to the parental strain. t ...200818838821
a novel thermostable arylesterase from the archaeon sulfolobus solfataricus p1: purification, characterization, and expression.a novel thermostable arylesterase, a 35-kda monomeric enzyme, was purified from the thermoacidophilic archaeon sulfolobus solfataricus p1. the optimum temperature and ph were 94 degrees c and 7.0, respectively. the enzyme displayed remarkable thermostability: it retained 52% of its activity after 50 h of incubation at 90 degrees c. in addition, the purified enzyme showed high stability against denaturing agents, including various detergents, urea, and organic solvents. the enzyme has broad subst ...200818931117
analysis of several methods for the extraction of high quality dna from acetic acid bacteria in wine and vinegar for characterization by pcr-based methods.acetic acid bacteria (aab) are fastidious microorganisms with poor recovery in culture. culture-independent methods are currently under examination. good dna extraction is a strict requirement of these methods. we compared five methods for extracting the dna of aab directly from wine and vinegar samples. four matrices (white wine, red wine, superficial vinegar and submerged vinegar) contaminated with two aab strains belonging to acetobacter pasteurianus and gluconacetobacter hansenii were assaye ...200818950887
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).200919200331
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 ...200919251897
differentiation of species of the family acetobacteraceae by aflp dna fingerprinting: gluconacetobacter kombuchae is a later heterotypic synonym of gluconacetobacter hansenii.amplified fragment length polymorphism (aflp) dna fingerprinting was investigated as a tool for fast and accurate identification of acetic acid bacteria (aab) to the species level. one hundred and thirty five reference strains and 15 additional strains, representing 50 recognized species of the family acetobacteraceae, were subjected to aflp analysis using the restriction enzyme combination apai/taqi and the primer combination a03/t03. the reference strains had been previously subjected to eithe ...200919542117
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 ...200919577815
thermostable lipases from the extreme thermophilic anaerobic bacteria thermoanaerobacter thermohydrosulfuricus sol1 and caldanaerobacter subterraneus subsp. tengcongensis.two novel genes encoding for heat and solvent stable lipases from strictly anaerobic extreme thermophilic bacteria thermoanaerobacter thermohydrosulfuricus (liptth) and caldanaerobacter subterraneus subsp. tengcongensis (lipcst) were successfully cloned and expressed in e. coli. recombinant proteins were purified to homogeneity by heat precipitation, hydrophobic interaction, and gel filtration chromatography. unlike the enzymes from mesophile counterparts, enzymatic activity was measured at a br ...200919579003
enhanced production of bacterial cellulose by using a biofilm reactor and its material property analysis.bacterial cellulose has been used in the food industry for applications such as low-calorie desserts, salads, and fabricated foods. it has also been used in the paper manufacturing industry to enhance paper strength, the electronics industry in acoustic diaphragms for audio speakers, the pharmaceutical industry as filtration membranes, and in the medical field as wound dressing and artificial skin material. in this study, different types of plastic composite support (pcs) were implemented separa ...200919630969
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 ...200919638423
the lactamase engineering database: a critical survey of tem sequences in public databases.tem beta-lactamases are the main cause for resistance against beta-lactam antibiotics. sequence information about tem beta-lactamases is mainly found in the ncbi peptide database and tem mutation table at http://www.lahey.org/studies/temtable.asp. while the tem mutation table is manually curated by experts in the lactamase field, who guarantee reliable and consistent information, the rapidly growing sequence and annotation information from the ncbi peptide database is sometimes inconsistent. the ...200919698099
characterization of thermotolerant acetobacter pasteurianus strains and their quinoprotein alcohol dehydrogenases.we isolated several thermotolerant acetobacter species of which msu10 strain, identified as acetobacter pasteurianus, could grow well on agar plates at 41 degrees c, tolerate to 1.5% acetic acid or 4% ethanol at 39 degrees c, similarly seen with a. pasteurianus sku1108 previously isolated. the msu10 strain showed higher acetic acid productivity in a medium containing 6% ethanol at 37 degrees c than sku1108 while sku1108 strain could accumulate more acetic acid in a medium supplemented with 4-5% ...201019711069
in vivo methylation of mtdna reveals the dynamics of protein-mtdna interactions.to characterize the organization of mtdna-protein complexes (known as nucleoids) in vivo, we have probed the mtdna surface exposure using site-specific dna methyltransferases targeted to the mitochondria. we have observed that dna methyltransferases have different accessibility to different sites on the mtdna based on the levels of protein occupancy. we focused our studies on selected regions of mtdna that are believed to be major regulatory regions involved in transcription and replication. the ...200919740762
diversity of acetobacter pasteurianus strains isolated from solid-state fermentation of cereal vinegars.vinegar production is based on the acetification process by indigenous acetic acid bacteria (aab). among vinegar technologies, solid-state fermentation (ssf) processes are widespread in asian countries to produce vinegar at small-scale. in this study, 21 aab strains isolated from chinese cereal vinegars produced by ssf collected in different regions of china were characterized by enterobacterial repetitive intergenic consensus (eric)-pcr fingerprinting. isolates exhibited high degree of phenotyp ...201019924479
cloning and functional analysis of adhs gene encoding quinoprotein alcohol dehydrogenase subunit iii from acetobacter pasteurianus sku1108.the adhs gene which encodes the smallest subunit, subunit iii, of quinoprotein alcohol dehydrogenase (pqq-adh) from acetobacter pasteurianus sku1108 has been cloned and characterized. the role of this subunit on the function of pqq-adh was investigated by construction of adhs gene disruptant and mutants. the adhs gene disruptant completely lost its pqq-adh activity and acetate-producing ability but retained acetic acid toleration. in contrast, this disruptant grew well, even better than the wild ...201020096472
population dynamics of acetic acid bacteria during traditional wine vinegar production.the population dynamics of acetic acid bacteria in traditional vinegar production was determined in two independent vinegar plants at both the species and strain level. the effect of barrels made of four different woods upon the population dynamics was also determined. acetic acid bacteria were isolated on solid media and the species were identified by rflp-pcr of 16s rrna genes and confirmed by 16s rrna gene sequencing, while strains were typed by eric-pcr and (gtg)(5)-rep-pcr. the most widely ...201020117853
cloning and characterization of grpe in acetobacter pasteurianus nbrc 3283.the grpe gene in acetobacter pasteurianus nbrc 3283 was cloned and characterized, to elucidate the mechanism underlying the resistance of acetic acid bacteria to the stressors existing during acetic acid fermentation. this gene was found to be located in tandem with two related genes, appearing on the genome in the order grpe-dnak-dnaj. a sigma(32)-type promoter sequence was found in the upstream region of grpe. the relative transcription levels of grpe, dnak, and dnaj mrna were in the ratio of ...201020129077
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) ...201020141944
effect of barrel design and the inoculation of acetobacter pasteurianus in wine vinegar production.the traditional production of wine vinegar is a lengthy process with little or no microbiological control. the aim of this study was to shorten the acetification process via three different strategies: changes in wood type; barrel shape; and the inoculation of an acetobacter pasteurianus pure culture. the barrel shape was modified by constructing two prototypes with higher liquid-air interface. we compared the changes in acetic acid bacteria (aab) population dynamics in these barrels with those ...201020478638
innate immunity in drosophila: pathogens and pathways.following in the footsteps of traditional developmental genetics, research over the last 15 years has shown that innate immunity against bacteria and fungi is governed largely by two nf-kappab signal transduction pathways, toll and imd. antiviral immunity appears to stem from rna interference, whereas resistance against parasitoids is conferred by toll signaling. the identification of these post-transcriptional regulatory mechanisms and the annotation of most drosophila immunity genes have deriv ...200820485470
magnetospirillum bellicus sp. nov., a novel dissimilatory perchlorate-reducing alphaproteobacterium isolated from a bioelectrical reactor.previously isolated dissimilatory perchlorate-reducing bacteria (dprb) have been primarily affiliated with the betaproteobacteria. enrichments from the cathodic chamber of a bioelectrical reactor (ber) inoculated from creek water in berkeley, ca, yielded a novel organism most closely related to a previously described strain, wd (99% 16s rrna gene identity). strain vdy(t) has 96% 16s rrna gene identity to both magnetospirillum gryphiswaldense and magnetospirillum magnetotacticum, and along with s ...201020495050
cloning and characterization of clpb in acetobacter pasteurianus nbrc 3283.the clpb gene in acetobacter pasteurianus was cloned and characterized. although the clpb gene was transcribed in response to a temperature shift and exposure to ethanol, the clpb disruption mutant was only affected by high temperature, suggesting that the clpb protein is closely associated with heat resistance in a. pasteurianus.201020541119
antioxidant pathways are up-regulated during biological nitrogen fixation to prevent ros-induced nitrogenase inhibition in gluconacetobacter diazotrophicus.gluconacetobacter diazotrophicus, an endophyte isolated from sugarcane, is a strict aerobe that fixates n(2). this process is catalyzed by nitrogenase and requires copious amounts of atp. nitrogenase activity is extremely sensitive to inhibition by oxygen and reactive oxygen species (ros). however, the elevated oxidative metabolic rates required to sustain biological nitrogen fixation (bnf) may favor an increased production of ros. here, we explored this paradox and observed that ros levels are, ...201020697694
acetic acid fermentation of acetobacter pasteurianus: relationship between acetic acid resistance and pellicle polysaccharide formation.acetobacter pasteurianus strains ifo3283, sku1108, and msu10 were grown under acetic acid fermentation conditions, and their growth behavior was examined together with their capacity for acetic acid resistance and pellicle formation. in the fermentation process, the cells became aggregated and covered by amorphous materials in the late-log and stationary phases, but dispersed again in the second growth phase (due to overoxidation). the morphological change in the cells was accompanied by changes ...201020699583
double duty for a conserved glutamate in pyruvate decarboxylase: evidence of the participation in stereoelectronically controlled decarboxylation and in protonation of the nascent carbanion/enamine intermediate .pyruvate decarboxylase (pdc) catalyzes the nonoxidative decarboxylation of pyruvate into acetaldehyde and carbon dioxide and requires thiamin diphosphate (thdp) and a divalent cation as cofactors. recent studies have permitted the assignment of functional roles of active site residues; however, the underlying reaction mechanisms of elementary steps have remained hypothetical. here, a kinetic and thermodynamic single-step analysis in conjunction with x-ray crystallographic studies of pdc from zym ...201020715795
kinetic analysis of strains of lactic acid bacteria and acetic acid bacteria in cocoa pulp simulation media toward development of a starter culture for cocoa bean fermentation.the composition of cocoa pulp simulation media (psm) was optimized with species-specific strains of lactic acid bacteria (psm-lab) and acetic acid bacteria (psm-aab). also, laboratory fermentations were carried out in psm to investigate growth and metabolite production of strains of lactobacillus plantarum and lactobacillus fermentum and of acetobacter pasteurianus isolated from ghanaian cocoa bean heap fermentations, in view of the development of a defined starter culture. in a first step, a se ...201020889778
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 ...201020935116
the calculation of information and organismal complexity.it is difficult to measure precisely the phenotypic complexity of living organisms. here we propose a method to calculate the minimal amount of genomic information needed to construct organism (effective information) as a measure of organismal complexity, by using permutation and combination formulas and shannon's information concept.201020937149
the bacterial community in 'taberna' a traditional beverage of southern mexico.to characterize the bacterial community of taberna, an alcoholic traditional beverage from the southern part of mexico produced by the fermentation of the coyol palm sap (acrocomia aculeate).201021039665
characterization of rpoh in acetobacter pasteurianus nbrc3283.the rpoh in acetobacter pasteurianus nbrc3283 was characterized. it was revealed that the rpoh controls the expression of groel, dnakj, grpe, and clpb to different extents. in addition, the rpoh disruption mutant became apt to be affected by heat, ethanol, and acetic acid, indicating its importance in acetic acid fermentation.201121239225
distribution of genes encoding nucleoid-associated protein homologs in plasmids.bacterial nucleoid-associated proteins (naps) form nucleoprotein complexes and influence the expression of genes. recent studies have shown that some plasmids carry genes encoding nap homologs, which play important roles in transcriptional regulation networks between plasmids and host chromosomes. in this study, we determined the distributions of the well-known naps fis, h-ns, hu, ihf, and lrp and the newly found naps mvat and ndpa among the whole-sequenced 1382 plasmids found in gram-negative b ...201121350637
dynamics and species diversity of communities of lactic acid bacteria and acetic acid bacteria during spontaneous cocoa bean fermentation in vessels.to speed up research on the usefulness and selection of bacterial starter cultures for cocoa bean fermentation, a benchmark cocoa bean fermentation process under natural fermentation conditions was developed successfully. therefore, spontaneous fermentations of cocoa pulp-bean mass in vessels on a 20 kg scale were tried out in triplicate. the community dynamics and kinetics of these fermentations were studied through a multiphasic approach. microbiological analysis revealed a limited bacterial s ...201021356451
genome sequences of the high-acetic acid-resistant bacteria gluconacetobacter europaeus lmg 18890t and g. europaeus lmg 18494 (reference strains), g. europaeus 5p3, and gluconacetobacter oboediens 174bp2 (isolated from vinegar).bacteria of the genus gluconacetobacter are usually involved in the industrial production of vinegars with high acetic acid concentrations. we describe here the genome sequence of three gluconacetobacter europaeus strains, a very common bacterial species from industrial fermentors, as well as of a gluconacetobacter oboediens strain.201121441523
monitoring the bacterial community of maize silage stored in a bunker silo inoculated with enterococcus faecium, lactobacillus plantarum and lactobacillus buchneri.to monitor variations in the bacterial community and fermentation products of maize silage within and between bunker silos.201121447012
increased number of arginine-based salt bridges contributes to the thermotolerance of thermotolerant acetic acid bacteria, acetobacter tropicalis sku1100.thermotolerant acetic acid bacteria (aab), acetobacter tropicalis sku1100, can grow above 40°c. to investigate the basis of its thermotolerance, we compared the genome of a. tropicalis sku1100 with that of mesophilic aab strain acetobacter pasteurianus ifo3283-01. the comparative genomic study showed that amino acid substitutions from large to small residue and lys to arg occur in many orthologous genes. furthermore, comparative modeling study was carried out with the orthologous proteins betwee ...201121554859
Biochemical and Mutational Studies of the Bacillus cereus CECT 5050T Formamidase Support the Existence of a C-E-E-K Tetrad in Several Members of the Nitrilase Superfamily.Formamidases (EC 3.5.1.49) are poorly characterized proteins. In spite of this scarce knowledge, ammonia has been described as playing a central role in the pathogenesis of human pathogens such as Helicobacter pylori, for which formamidase has been shown to participate in the nitrogen metabolic pathway. Sequence analysis has revealed that at least two different groups of formamidases are classified as EC 3.5.1.49: on the one hand, the derivatives of the FmdA-AmdA superfamily, which are the best ...201121705545
microbial dynamics during aerobic exposure of corn silage stored under oxygen barrier or polyethylene films.the aims were to compare the effects of sealing forage maize with a new oxygen barrier film or with a conventional polyethylene film. this comparison would be during both ensilage and subsequent exposure of silage to air, and would include chemical, microbiological and molecular (dna and rna) assessments. the forage was inoculated with a mixture of lactobacillus buchneri, lb. plantarum, and enterococcus faecium and ensiled in polyethylene (pe) and oxygen barrier (ob) plastic bags. the oxygen per ...201121821764
spontaneous organic cocoa bean box fermentations in brazil are characterized by a restricted species diversity of lactic acid bacteria and acetic acid bacteria.spontaneous organic cocoa bean box fermentations were carried out on two different farms in brazil. physical parameters, microbial growth, bacterial species diversity [mainly lactic acid bacteria (lab) and acetic acid bacteria (aab)], and metabolite kinetics were monitored, and chocolates were produced from the fermented dry cocoa beans. the main end-products of the catabolism of the pulp substrates (glucose, fructose, and citric acid) by yeasts, lab, and aab were ethanol, lactic acid, mannitol, ...201121839382
molecular cloning and characterization of two inducible nad(+)-adh genes encoding nad(+)-dependent alcohol dehydrogenases from acetobacter pasteurianus sku1108.the cytosolic nad(+)-dependent alcohol dehydrogenases (nad(+)-adhs) are induced in the quinoprotein adh-(pqq-adh) defective acetobacter pasteurianus sku1108 mutant during growth in an ethanol medium. the adhi and adhii genes, which encode nad(+)-adh i and adh ii, respectively, of this strain have been cloned and characterized. sequence analyses have revealed that the adhi gene consists of 1029bp coding for 342 amino acids, which share 99.71% identity with the same protein from a. pasteurianus if ...201121843965
diversity of acetic acid bacteria present in healthy grapes from the canary islands.the identification of acetic acid bacteria (aab) from sound grapes from the canary islands is reported in the present study. no direct recovery of bacteria was possible in the most commonly used medium, so microvinifications were performed on grapes from tenerife, la palma and lanzarote islands. up to 396 aab were isolated from those microvinifications and identified by 16s rrna gene sequencing and phylogenetic analysis. with this method, acetobacter pasteurianus, acetobacter tropicalis, glucono ...201121903289
species diversity, community dynamics, and metabolite kinetics of the microbiota associated with traditional ecuadorian spontaneous cocoa bean fermentations.traditional fermentations of the local ecuadorian cocoa type nacional, with its fine flavor, are carried out in boxes and on platforms for a short time. a multiphasic approach, encompassing culture-dependent and -independent microbiological analyses of fermenting cocoa pulp-bean samples, metabolite target analyses of both cocoa pulp and beans, and sensory analysis of chocolates produced from the respective fermented dry beans, was applied for the investigation of the influence of these fermentat ...201121926224
molecular determinants for substrate selectivity of ω-transaminases.ω-transaminase (ω-ta) is an industrially important enzyme for production of chiral amines. about 20 (s)-specific ω-tas known to date show remarkably similar substrate selectivity characterized by stringent steric constraint precluding entry of a substituent larger than an ethyl group in the small binding pocket (s) and dual recognition of an aromatic substituent as well as a carboxylate group in the large pocket (l). the strictly defined substrate selectivity of the available ω-tas remains a lim ...201121983703
Genome-wide phylogenetic analysis of differences in thermotolerance among closely related Acetobacter pasteurianus strains.Acetobacter pasteurianus is a Gram-negative strictly aerobic bacterium that is widely used for the industrial production of vinegar. Three Acetobacter pasteurianus strains, SKU1108, NBRC 3283 and IFO 3191, have the same 16S rRNA sequence (100?% sequence identity) but show differences in thermotolerance. To clarify the relationships between phylogeny and thermotolerance of these strains, genome-wide analysis of these three strains was performed. Concatenated phylogenetic analysis of a dataset of ...201222016572
Gene cloning and characterization of a-amino acid ester acyl transferase in Empedobacter brevis ATCC14234 and Sphingobacterium siyangensis AJ2458.The gene encoding a-amino acid ester acyl transferase (AET), the enzyme that catalyzes the peptide-forming reaction from amino acid methyl esters and amino acids, was cloned from Empedobacter brevis ATCC14234 and Sphingobacterium siyangensis AJ2458 and expressed in Escherichia coli. This is the first report on the aet gene. It encodes a polypeptide composed of 616 (ATCC14234) and 619 (AJ2458) amino acids residues. The V(max) values of these recombinant enzymes during the catalysis of L-alanyl-L- ...201122056425
amino ester hydrolase from xanthomonas campestris pv. campestris, atcc 33913 for enzymatic synthesis of ampicillin.a-amino ester hydrolases (aeh) are a small class of proteins, which are highly specific for hydrolysis or synthesis of a-amino containing amides and esters including ß-lactam antibiotics such as ampicillin, amoxicillin, and cephalexin. a blast search revealed the sequence of a putative glutaryl 7-aminocephalosporanic acid (gl-7-aca) acylase 93% identical to a known aeh from xanthomonas citri. the gene, termed gaa, was cloned from the genomic dna of xanthomonas campestris pv. campestris sp. strai ...201022087071
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 ...201122099947
assessment of bacterial diversity in selected philippine fermented food products through pcr-dgge.the bacterial population in several philippine fermented food preparations was assessed by pcr-denaturing gradient gel electrophoresis (pcr-dgge) of the 16s rrna gene (16s rdna). genomic dna was isolated directly from alamang (fermented shrimp paste), burong isda (fermented fish and rice), burong hipon (fermented shrimp and rice), burong mustasa (fermented mustard leaves), tuba (sugar cane wine), suka (vinegar) and sinamak (spiced vinegar) using one of two protocols, namely - mobio dna extractio ...201122146687
proteome analysis of acetobacter pasteurianus during acetic acid fermentation.acetic acid bacteria (aab) are gram-negative, strictly aerobic microorganisms that show a unique resistance to ethanol (etoh) and acetic acid (ach). members of the acetobacter and gluconacetobacter genera are capable of transforming etoh into ach via the alcohol dehydrogenase (adh) and aldehyde dehydrogenase (aldh) enzymes and are used for the industrial production of vinegar. several mechanisms have been proposed to explain how aab resist high concentrations of ach, such as the assimilation of ...201122155126
azospirillum genomes reveal transition of bacteria from aquatic to terrestrial environments.fossil records indicate that life appeared in marine environments ∼3.5 billion years ago (gyr) and transitioned to terrestrial ecosystems nearly 2.5 gyr. sequence analysis suggests that "hydrobacteria" and "terrabacteria" might have diverged as early as 3 gyr. bacteria of the genus azospirillum are associated with roots of terrestrial plants; however, virtually all their close relatives are aquatic. we obtained genome sequences of two azospirillum species and analyzed their gene origins. while m ...201122216014
identification of yeast and acetic acid bacteria isolated from the fermentation and acetification of persimmon (diospyros kaki).persimmon (diospyros kaki) is a seasonal fruit with important health benefits. in this study, persimmon use in wine and condiment production was investigated using molecular methods to identify the yeast and acetic acid bacteria (aab) isolated from the alcoholic fermentation and acetification of the fruit. alcoholic fermentation was allowed to occur either spontaneously, or by inoculation with a commercial saccharomyces cerevisiae wine strain, while acetification was always spontaneous; all thes ...201222265289
bacterial cocaine esterase: a protein-based therapy for cocaine overdose and addiction.cocaine is highly addictive and there are no pharmacotherapeutic drugs available to treat acute cocaine toxicity or chronic abuse. antagonizing an inhibitor such as cocaine using a small molecule has proven difficult. the alternative approach is to modify cocaine's pharmacokinetic properties by sequestering or hydrolyzing it in serum and limiting access to its sites of action. we took advantage of a bacterial esterase (coce) that has evolved to hydrolyze cocaine and have developed it as a therap ...201222300094
potential for development of an escherichia coli-based biosensor for assessing bioavailable methionine: a review.methionine is an essential amino acid for animals and is typically considered one of the first limiting amino acids in animal feed formulations. methionine deficiency or excess in animal diets can lead to sub-optimal animal performance and increased environmental pollution, which necessitates its accurate quantification and proper dosage in animal rations. animal bioassays are the current industry standard to quantify methionine bioavailability. however, animal-based assays are not only time con ...201022319312
interkingdom gene transfer may contribute to the evolution of phytopathogenicity in botrytis cinerea.the ascomycete botrytis cinerea is a phytopathogenic fungus infecting and causing significant yield losses in a number of crops. the genome of b. cinerea has been fully sequenced while the importance of horizontal gene transfer (hgt) to extend the host range in plant pathogenic fungi has been recently appreciated. however, recent data confirm that the b. cinerea fungus shares conserved virulence factors with other fungal plant pathogens with narrow host range. therefore, interkingdom hgt may con ...201222346340
isolation, characterization and optimization of indigenous acetic acid bacteria and evaluation of their preservation methods.acetic acid bacteria (aab) are useful in industrial production of vinegar. the present study aims at isolation and identification of acetic acid bacteria with characterization, optimization, and evaluation of their acetic acid productivity.201022347549
isolation and preliminary characterization of amino acid substitution mutations that increase the activity of the osmoregulated prop protein of salmonella enterica serovar typhimurium.in enterobacteriaceae, the prop protein, which takes up proline and glycine betaine, is subject to a post-translational control mechanism that increases its activity at high osmolarity. in order to investigate the osmoregulatory mechanism of the salmonella enterica prop, we devised a positive selection for mutations that conferred increased activity on this protein at low osmolarity. the selection involved the isolation of mutations in a proline auxotroph that resulted in increased accumulation ...201222360681
on-farm implementation of a starter culture for improved cocoa bean fermentation and its influence on the flavour of chocolates produced thereof.cocoa bean fermentations controlled by means of starter cultures were introduced on several farms in two different cocoa-producing regions (west africa and southeast asia). two starter culture mixtures were tested, namely one composed of saccharomyces cerevisiae h5s5k23, lactobacillus fermentum 222, and acetobacter pasteurianus 386b (three heaps and one box), and another composed of l. fermentum 222 and a. pasteurianus 386b (seven heaps and one box). in all starter culture-added cocoa bean ferme ...201122365351
acetobacter pasteurianus strain ab0220: cultivability and phenotypic stability over 9 years of preservation.acetobacter species are members of the α-subclass of proteobacteria, which harbors a large number of bacteria recalcitrant to cultivation. strain ab0220 was isolated from a superficial acetification system and preserved for 9 years by short and long time methods. under short time preservation it was estimated that 540.54 number of generations occurred, whereas in long time preservation conditions the number of generations was 17.40. ethanol oxidation to acetic acid was stable and confirmed, as w ...201222441885
prokaryotic squalene-hopene cyclases can be converted to citronellal cyclases by single amino acid exchange.squalene-hopene cyclases (shcs) are prokaryotic enzymes that catalyse the cyclisation of the linear precursor squalene to pentacyclic hopene. recently, we discovered that a shc cloned from zymomonas mobilis (zmo-1548 gene product) has the unique property to cyclise the monoterpenoid citronellal to isopulegol. in this study, we performed saturation mutagenesis of three amino acids of the catalytic centre of zmo-1548 (f428, f486 and w555), which had been previously identified to interact with enzy ...201322526778
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 ...201222572876
phylogenetic analysis of a spontaneous cocoa bean fermentation metagenome reveals new insights into its bacterial and fungal community diversity.this is the first report on the phylogenetic analysis of the community diversity of a single spontaneous cocoa bean box fermentation sample through a metagenomic approach involving 454 pyrosequencing. several sequence-based and composition-based taxonomic profiling tools were used and evaluated to avoid software-dependent results and their outcome was validated by comparison with previously obtained culture-dependent and culture-independent data. overall, this approach revealed a wider bacterial ...201222666442
comparative analysis of two phenotypically-similar but genomically-distinct burkholderia cenocepacia-specific bacteriophages.genomic analysis of bacteriophages infecting the burkholderia cepacia complex (bcc) is an important preliminary step in the development of a phage therapy protocol for these opportunistic pathogens. the objective of this study was to characterize kl1 (vb_bces_kl1) and ah2 (vb_bces_ah2), two novel burkholderia cenocepacia-specific siphoviruses isolated from environmental samples.201222676492
the clpb gene is involved in the stress response of myxococcus xanthus during vegetative growth and development.the clp/hsp100 family of molecular chaperones is ubiquitous in both prokaryotes and eukaryotes. these proteins play important roles in refolding, disaggregating and degrading proteins damaged by stress. as a subclass of the clp/hsp100 family, clpb has been shown to be involved in various stress responses as well as other functions in bacteria. in the present study, we investigated the role of a predicted clpb-encoding gene, mxan5092, in the stress response during vegetative growth and developmen ...201222790397
oasis: an automated program for global investigation of bacterial and archaeal insertion sequences.insertion sequences (iss) are simple transposable elements present in most bacterial and archaeal genomes and play an important role in genomic evolution. the recent expansion of sequenced genomes offers the opportunity to study iss comprehensively, but this requires efficient and accurate tools for is annotation. we have developed an open-source program called oasis, or optimized annotation system for insertion sequences, which automatically annotates iss within sequenced genomes. oasis annotat ...201222904081
ehrlichia chaffeensis tandem repeat proteins and ank200 are type 1 secretion system substrates related to the repeats-in-toxin exoprotein family.ehrlichia chaffeensis has type 1 and 4 secretion systems (t1ss and t4ss), but the substrates have not been identified. potential substrates include secreted tandem repeat protein (trp) 47, trp120, and trp32, and the ankyrin repeat protein, ank200, that are involved in molecular host-pathogen interactions including dna binding and a network of protein-protein interactions with host targets associated with signaling, transcriptional regulation, vesicle trafficking, and apoptosis. in this study we ...201122919588
identification of a five-oxidoreductase-gene cluster from acetobacter pasteurianus conferring ethanol-dependent acidification in escherichia coli.acetobacter pasteurianus, a gram-negative bacterium belonging to the α-divison of proteobacteria, produces acetic acid through ethanol oxidation. a genomic bank of a. pasteurianus 386b dna was cloned in the low-copy cosmid prg930cm vector and the resulting clones were screened for the production of protease using the skimmed-milk agar assay whereby a clearing zone around the inoculated spots indicates casein degradation. several positive clones were selected and restriction analysis revealed tha ...201222950009
a mutation of the rna polymerase β' subunit (rpoc) confers cephalosporin resistance in bacillus subtilis.in bacteria, mutations affecting the major catalytic subunits of rna polymerase (encoded by rpob and rpoc) emerge in response to a variety of selective pressures. here we isolated a bacillus subtilis strain with high-level resistance to cefuroxime (cef). whole-genome resequencing revealed only one missense mutation affecting an invariant residue in close proximity to the c-terminal dna-binding domain of rpoc (g1122d). genetic reconstruction experiments demonstrate that this substitution is suffi ...201323070162
numerical analysis of phenotypic features and protein gel electrophoregrams of a wide variety of acetobacter strains. proposal for the improvement of the taxonomy of the genus acetobacter beijerinck 1898, 215.ninety-eight strains, representing all acetobacter species and subspecies from the approved lists of bacterial names (skerman et al., 1980), were examined in a numerical analysis of 177 phenotypic features and compared to ninety-eight gluconobacter and seven frateuria strains. four phenons could be delineated, corresponding to frateuria (phenon 1), a. aceti subsp. liquefaciens (phenon 2), gluconobacter (phenon 3) and acetobacter minus a. aceti subsp. liquefaciens (phenon 4). acetobacter, frateur ...198323194734
comparative genomic analysis of the microbiome [corrected] of herbivorous insects reveals eco-environmental adaptations: biotechnology applications.metagenome analysis of the gut symbionts of three different insects was conducted as a means of comparing taxonomic and metabolic diversity of gut microbiomes to diet and life history of the insect hosts. a second goal was the discovery of novel biocatalysts for biorefinery applications. grasshopper and cutworm gut symbionts were sequenced and compared with the previously identified metagenome of termite gut microbiota. these insect hosts represent three different insect orders and specialize on ...201323326236
influence of organic solvents on enzymatic asymmetric carboligations.the asymmetric mixed carboligation of aldehydes with thiamine diphosphate (thdp)-dependent enzymes is an excellent example where activity as well as changes in chemo- and stereoselectivity can be followed sensitively. to elucidate the influence of organic additives in enzymatic carboligation reactions of mixed 2-hydroxy ketones, we present a comparative study of six thdp-dependent enzymes in 13 water-miscible organic solvents under equivalent reaction conditions. the influence of the additives o ...201223349644
combined fluxomics and transcriptomics analysis of glucose catabolism via a partially cyclic pentose phosphate pathway in gluconobacter oxydans 621h.in this study, the distribution and regulation of periplasmic and cytoplasmic carbon fluxes in gluconobacter oxydans 621h with glucose were studied by (13)c-based metabolic flux analysis ((13)c-mfa) in combination with transcriptomics and enzyme assays. for (13)c-mfa, cells were cultivated with specifically (13)c-labeled glucose, and intracellular metabolites were analyzed for their labeling pattern by liquid chromatography-mass spectrometry (lc-ms). in growth phase i, 90% of the glucose was oxi ...201323377928
microbe-dependent and nonspecific effects of procedures to eliminate the resident microbiota from drosophila melanogaster.comparisons of animals bearing and lacking microorganisms can offer valuable insight into the interactions between animal hosts and their resident microbiota. most hosts are naturally infected, and therefore, these comparisons require specific procedures (e.g., antibiotic treatment or physical exclusion of microorganisms) to disrupt the microbiota, but the potential for confounding nonspecific effects of the procedure on the traits of the host exists. microbe-dependent and nonspecific effects ca ...201323475620
structural studies of pseudomonas and chromobacterium ω-aminotransferases provide insights into their differing substrate specificity.the crystal structures and inhibitor complexes of two industrially important ω-aminotransferase enzymes from pseudomonas aeruginosa and chromobacterium violaceum have been determined in order to understand the differences in their substrate specificity. the two enzymes share 30% sequence identity and use the same amino acceptor, pyruvate; however, the pseudomonas enzyme shows activity towards the amino donor β-alanine, whilst the chromobacterium enzyme does not. both enzymes show activity toward ...201323519665
adaptive mutation of acetobacter pasteurianus sku1108 enhances acetic acid fermentation ability at high temperature.in vitro adaptation is one of the most challenging subjects in biology to understand adaptive evolution. microbial adaptation to temperature is not only interesting in terms of understanding the adaptation mechanism, but also useful for industrial applications. in this study, we attempted the in vitro adaptation of acetobacter pasteurianus sku1108 by repeating its cultivation under high-temperature acetic acid fermentation conditions. as a result, thermo-adapted strains having the higher ferment ...201323524057
draft genome sequence of dihydroxyacetone-producing gluconobacter thailandicus strain nbrc 3255.here, we report the draft genome sequence of the acetic acid bacterium glucnobacter thailandicus strain nbrc 3255. the draft genome sequence is composed of 109 contigs in 3,305,227 bp and contains 3,225 protein-coding genes. two paralogous sets of sldab operons, which are responsible for dihydroxyacetone production from glycerol, were identified.201323580707
a survey of fermentation products and bacterial communities in corn silage produced in a bunker silo in china.to evaluate the current practice of corn silage management in china, samples of bunker-made silage were collected from 14 farms within a 500-km radius of beijing for the analysis of fermentation products and bacterial communities. mean values for dry matter (dm) content were as low as 250 g/kg in both corn stover (st) and whole crop corn (wc) silages, and ph values averaged 4.48 and 3.73, respectively. only three of the 14 silages exhibited a lactic-to-acetic acid ratio > 1.0, indicating that th ...201423638801
hanseniaspora opuntiae, saccharomyces cerevisiae, lactobacillus fermentum, and acetobacter pasteurianus predominate during well-performed malaysian cocoa bean box fermentations, underlining the importance of these microbial species for a successful cocoa bean fermentation process.two spontaneous malaysian cocoa bean box fermentations (one farm, two plantation plots) were investigated. physical parameters, microbial community dynamics, yeast and bacterial species diversity [mainly lactic acid bacteria (lab) and acetic acid bacteria (aab)], and metabolite kinetics were monitored, and chocolates were produced from the respective fermented dry cocoa beans. similar microbial growth and metabolite profiles were obtained for the two fermentations. low concentrations of citric a ...201323664257
acetobacter strains isolated during the acetification of blueberry (vaccinium corymbosum l.) wine.highbush blueberries (vaccinium corymbosum l.) are known to have positive health benefits. the production of blueberry vinegar is one method to preserve this seasonal fruit and allow extended consumption. in this study, blueberry wine acetification was performed with naturally occurring micro-organisms and with an inoculated acetobacter cerevisiae strain. acetifications were carried out in triplicate using the schützenbach method. the successful spontaneous processes took up to 66% more time tha ...201323682741
partial venom gland transcriptome of a drosophila parasitoid wasp, leptopilina heterotoma, reveals novel and shared bioactive profiles with stinging hymenoptera.analysis of natural host-parasite relationships reveals the evolutionary forces that shape the delicate and unique specificity characteristic of such interactions. the accessory long gland-reservoir complex of the wasp leptopilina heterotoma (figitidae) produces venom with virus-like particles. upon delivery, venom components delay host larval development and completely block host immune responses. the host range of this drosophila endoparasitoid notably includes the highly-studied model organis ...201323688557
microbial community structure of three traditional zambian fermented products: mabisi, chibwantu and munkoyo.around the world, raw materials are converted into fermented food products through microbial and enzymatic activity. products are typically produced using a process known as batch culture, where small volumes of an old culture are used to initiate a fresh culture. repeated over many years, and provided samples are not shared among producers, batch culture techniques allow for the natural evolution of independent microbial ecosystems. while these products form an important part of the diets of ma ...201323691123
the microbiology of malting and brewing.brewing beer involves microbial activity at every stage, from raw material production and malting to stability in the package. most of these activities are desirable, as beer is the result of a traditional food fermentation, but others represent threats to the quality of the final product and must be controlled actively through careful management, the daily task of maltsters and brewers globally. this review collates current knowledge relevant to the biology of brewing yeast, fermentation manage ...201323699253
acetobacter malorum and acetobacter cerevisiae identification and quantification by real-time pcr with taqman-mgb probes.the identification and quantification of acetobacter malorum and acetobacter cerevisiae in wine and vinegar were performed using the real-time pcr (rt-pcr) with two taqman-mgb probes designed to amplify the internal transcribed spacer (its) region between the 16s-23s rrna genes. the primers and probes were highly specific, with a detection limit of 10² cells/ml for both species, and the efficiency of the technique was >80%. the rt-pcr technique with these two new taqman-mgb probes, together with ...201323764217
effects of 8 chemical and bacterial additives on the quality of corn silage.this project aimed to evaluate the effects 8 additives on the fermentation, dry matter (dm) losses, nutritive value, and aerobic stability of corn silage. corn forage harvested at 31% dm was chopped (10mm) and treated with (1) deionized water (control); (2) buchneri 500 (buc; 1×10(5) cfu/g of pediococcus pentosaceus 12455 and 4×10(5) cfu/g of lactobacillus buchneri 40788; lallemand animal nutrition, milwaukee, wi); (3) sodium benzoate (ben; 0.1% of fresh forage); (4) silage savor acid mixture (s ...201323810597
separation and characterization of the immunostimulatory components in unpolished rice black vinegar (kurozu).unpolished rice black vinegar (kurozu), a traditional japanese vinegar, is considered to have beneficial health effects. kurozu is produced via a static fermentation process involving the saccharification of rice by aspergillus oryzae, alcohol fermentation by saccharomyces cerevisiae, and the oxidation of ethanol to acetic acid by acetic acid bacteria such as acetobacter pasteurianus. since this process requires about 6 months' fermentation and then over a year of aging, most of these organisms ...201323810669
evidence for a key role of cytochrome bo3 oxidase in respiratory energy metabolism of gluconobacter oxydans.the obligatory aerobic acetic acid bacterium gluconobacter oxydans oxidizes a variety of substrates in the periplasm by membrane-bound dehydrogenases, which transfer the reducing equivalents to ubiquinone. two quinol oxidases, cytochrome bo3 and cytochrome bd, then catalyze transfer of the electrons from ubiquinol to molecular oxygen. in this study, mutants lacking either of these terminal oxidases were characterized. deletion of the cydab genes for cytochrome bd had no obvious influence on grow ...201323852873
influencing cocoa flavour using pichia kluyveri and kluyveromyces marxianus in a defined mixed starter culture for cocoa fermentation.the potential impact of aromatic and pectinolytic yeasts on cocoa flavour was investigated using two defined mixed starter cultures encompassing strains of pichia kluyveri and kluyveromyces marxianus for inoculating cocoa beans in small scale tray fermentations. samples for microbial and metabolite analysis were collected at 12-24 hour intervals during 120 h of fermentation. yeast isolates were grouped by (gtg)5-based rep-pcr fingerprinting and identified by sequencing of the d1/d2 region of the ...201323866910
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 ...201323902333
identification and characterization of three novel lipases belonging to families ii and v from anaerovibrio lipolyticus 5st.following the isolation, cultivation and characterization of the rumen bacterium anaerovibrio lipolyticus in the 1960s, it has been recognized as one of the major species involved in lipid hydrolysis in ruminant animals. however, there has been limited characterization of the lipases from the bacterium, despite the importance of understanding lipolysis and its impact on subsequent biohydrogenation of polyunsaturated fatty acids by rumen microbes. this study describes the draft genome of anaerovi ...201323950883
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 ...201323961227
brazilian kefir: structure, microbial communities and chemical composition.microbial ecology and chemical composition of brazilian kefir beverage was performed. the microorganisms associated with brazilian kefir were investigated using a combination of phenotypic and genotypic methods. a total of 359 microbial isolates were identified. lactic acid bacteria (60.5%) were the major isolated group identified, followed by yeasts (30.6%) and acetic acid bacteria (8.9%). lactobacillus paracasei (89 isolates), lactobacillus parabuchneri (41 isolates), lactobacillus casei (32 i ...201124031681
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