Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| maintenance of deltaph by a butanol-tolerant mutant of clostridium beijerinckii. | the isolation of clostridium beijerinckii mutants that are more tolerant of butanol than the wild-type offered the opportunity to investigate whether the membrane activities which are required for maintaining the transmembrane deltaph (the difference in ph between the cellular interior and exterior) are sensitive targets of butanol toxicity. the deltaph was measured by the accumulation of [14c]benzoate using late-exponential-phase cells which were suspended in citrate/phosphate buffer at ph 5 (t ... | 2005 | 15699209 |
| improving performance of a gas stripping-based recovery system to remove butanol from clostridium beijerinckii fermentation. | the effect of factors such as gas recycle rate, bubble size, presence of acetone, and ethanol in the solution/broth were investigated in order to remove butanol from model solution or fermentation broth (also called acetone butanol ethanol or abe or solvents). butanol (8 g l(-1), model solution, fig. 2) stripping rate was found to be proportional to the gas recycle rate. in the bubble size range attempted (< 0.5 and 0.5-5.0 mm), the bubble size did not have any effect on butanol removal rate (fi ... | 2005 | 15806382 |
| evidence for the presence of an alternative glucose transport system in clostridium beijerinckii ncimb 8052 and the solvent-hyperproducing mutant ba101. | the effects of substrate analogs and energy inhibitors on glucose uptake and phosphorylation by clostridium beijerinckii provide evidence for the operation of two uptake systems: a previously characterized phosphoenolpyruvate-dependent phosphotransferase system (pts) and a non-pts system probably energized by the transmembrane proton gradient. in both wild-type c. beijerinckii ncimb 8052 and the butanol-hyperproducing mutant ba101, pts activity declined at the end of exponential growth, while gl ... | 2005 | 15933048 |
| acetone, isopropanol, and butanol production by clostridium beijerinckii (syn. clostridium butylicum) and clostridium aurantibutyricum. | thirty-four strains representing 15 species of anaerobic bacteria were screened for acetone, isopropanol, and n-butanol (solvent) production. under our culture conditions, several strains of clostridium beijerinckii and c. aurantibutyricum produced at least 40 mm n-butanol (c. acetobutylicum strains produced up to 41 mm n-butanol under similar conditions). both solvent-producing and non-solvent-producing strains of c. beijerinckii have high dna homology with a reference strain of c. beijerinckii ... | 1983 | 16346237 |
| acidic conditions are not obligatory for onset of butanol formation by clostridium beijerinckii (synonym, c. butylicum). | factors that may initiate the metabolic transition for butanol production were investigated in batch cultures of clostridium beijerinckii (synonym, clostridium butylicum) vpi 13436. cultures maintained at ph 6.8 produced nearly as much butanol as those incubated without ph control, indicating that neither a change in the culture ph nor acid conditions per se are always required to initiate solvent formation. acetate and butyrate levels at the onset of butanol production were dependent on the ph ... | 1983 | 16346358 |
| butanol-ethanol dehydrogenase and butanol-ethanol-isopropanol dehydrogenase: different alcohol dehydrogenases in two strains of clostridium beijerinckii (clostridium butylicum). | alcohol-producing strains of clostridium beijerinckii (clostridium butylicum) produce, besides acetone, either n-butanol and ethanol or n-butanol, ethanol, and isopropanol as their characteristic products. alcohol dehydrogenase has been isolated from a strain (nrrl b593) of c. beijerinckii producing isopropanol and from a strain (nrrl b592) not producing isopropanol. butanol-ethanol dehydrogenase activities were present in both strains, but isopropanol dehydrogenase activity was present only in ... | 1987 | 16347317 |
| expression of solvent-forming enzymes and onset of solvent production in batch cultures of clostridium beijerinckii ("clostridium butylicum"). | clostridium beijerinckii ("clostridium butylicum") nrrl b592 and nrrl b593 were grown in batch cultures without ph control. the use of more sensitive and accurate procedures for the determination of solvents in cultures led to the recognition of the onset of solvent production about 2 h earlier than the previously assigned point and at a higher culture ph for both strains. reliable assays for solvent-forming enzyme activities in cell extracts have also been developed. the results showed that act ... | 1988 | 16347575 |
| anaerobic desulfonation of 4-tolylsulfonate and 2-(4-sulfophenyl) butyrate by a clostridium sp. | alkyl- and arylsulfonates were tested as sole added sources of sulfur for the growth of enrichment cultures under strictly anaerobic denitrifying or fermentative conditions. cultures that utilized taurine, ethylsulfonate, the dyestuffs orange ii and acid red i, tolylsulfonate, 2-(4-sulfophenyl)butyrate (spb), a dialkyltetralinesulfonate, and 1-(4-sulfophenyl)octane were readily obtained. we chose to work with the simple aromatic compounds and isolated a fermentative bacterium, strain ev4, which ... | 1996 | 16535305 |
| long-term continuous cultivation of clostridium beijerinckii in a two-stage chemostat with on-line solvent removal. | a two-stage continuous cultivation experiment with clostridium beijerinckii nrrl b592 is described. this strain maintained its ability to produce neutral solvents (acetone, n-butanol, and ethanol) at an overall dilution rate of 0.13 h(sup-1) and achieved an average overall solvent concentration of 9.27 g/liter and an overall solvent productivity of 1.24 g/liter/h for more than 100 overall retention times. the experiment was performed without ph control on a semisynthetic medium containing yeast ... | 1996 | 16535396 |
| enhanced butanol production by clostridium beijerinckii ba101 grown in semidefined p2 medium containing 6 percent maltodextrin or glucose. | dramatically elevated levels of butanol and acetone resulted in higher butanol and total solvent yields for hyperamylolytic clostridium beijerinckii ba101 relative to the ncimb 8052 parent strain grown in semidefined p2 medium containing either 6% glucose or star-dri 5 maltodextrin. c. beijerinckii ba101 consistently produced on the order of 19 g of butanol per liter in 20-liter batch fermentations. this represents a greater than 100% increase in butanol concentration by the ba101 strain compare ... | 1997 | 16535628 |
| molecular cloning, nucleotide sequencing, and expression of genes encoding alcohol dehydrogenases from the thermophile thermoanaerobacter brockii and the mesophile clostridium beijerinckii. | proteins play a pivotal role in thermophily. comparing the molecular properties of homologous proteins from thermophilic and mesophilic bacteria is important for understanding the mechanisms of microbial adaptation to extreme environments. the thermophile thermoanaerobacter (thermoanaerobium) brockii and the mesophile clostridium beijerinckii contain an nadp(h)-linked, zinc-containing secondary alcohol dehydrogenase (tbadh and cbadh) showing a similarly broad substrate range. the structural gene ... | 1997 | 16887600 |
| characterisation of a transposon-induced pleiotropic mutant of clostridium acetobutylicum p262. | transposon-induced metronidazole resistance was used as a selection system for the isolation of clostridium acetobutylicum p262 mutants with altered electron transport pathways. the metronidazole resistant transconjugant of interest, mutant 3r, displayed resistance to dna damaging agents, uv and bleomycin, and harboured a single transposon insertion within a structural gene, designated sum(susceptibility to metronidazole). the sum gene encoded a 334 amino-acid protein, with 36% identity and 57-5 ... | 1997 | 16887617 |
| type iv pili-dependent gliding motility in the gram-positive pathogen clostridium perfringens and other clostridia. | bacteria can swim in liquid media by flagellar rotation and can move on surfaces via gliding or twitching motility. one type of gliding motility involves the extension, attachment and retraction of type iv pili (tfp), which pull the bacterium towards the site of attachment. tfp-dependent gliding motility has been seen in many gram-negative bacteria but not in gram-positive bacteria. recently, the genome sequences of three strains of clostridium perfringens have been completed and we identified g ... | 2006 | 16999833 |
| a single proline substitution is critical for the thermostabilization of clostridium beijerinckii alcohol dehydrogenase. | analysis of the three-dimensional structures of three closely related mesophilic, thermophilic, and hyperthermophilic alcohol dehydrogenases (adhs) from the respective microorganisms clostridium beijerinckii (cbadh), entamoeba histolytica (ehadh1), and thermoanaerobacter brockii (tbadh) suggested that a unique, strategically located proline residue (pro100) might be crucial for maintaining the thermal stability of ehadh1. to determine whether proline substitution at this position in tbadh and cb ... | 2007 | 17063493 |
| characterization of the sol operon in butanol-hyperproducing clostridium saccharoperbutylacetonicum strain n1-4 and its degeneration mechanism. | the solventogenic sol operon consisting of bld, ctfa, ctfb, and adc was cloned from clostridium saccharoperbutylacetonicum strain n1-4. these genes share as high as 95-98% similarity with the corresponding sol genes of clostridium beijerinckii ncimb 8052. the n1-4 sol gene cluster was transcribed in a polycistronic manner under the control of two promoters, and its transcription was highly induced during solventogenesis. strain dgn3-4, the degenerated strain derived from n1-4, maintained the sol ... | 2007 | 17213660 |
| butanol production from agricultural residues: impact of degradation products on clostridium beijerinckii growth and butanol fermentation. | during pretreatment and hydrolysis of fiber-rich agricultural biomass, compounds such as salts, furfural, hydroxymethyl furfural (hmf), acetic, ferulic, glucuronic, rho-coumaric acids, and phenolic compounds are produced. clostridium beijerinckii ba101 can utilize the individual sugars present in lignocellulosic [e.g., corn fiber, distillers dry grain solubles (ddgs), etc] hydrolysates such as cellobiose, glucose, mannose, arabinose, and xylose. in these studies we investigated the effect of som ... | 2007 | 17274071 |
| changes in numbers and kinds of bacteria during a chickpea submerged fermentation used as a leavening agent for bread production. | the microflora developed during a submerged fermentation of coarsely ground chickpea (cicer arietinum l.) in water (primary starter) and during raising a dough from wheat flour (adapted starter) was studied. in the fermenting liquid, only populations of bacillus and clostridium developed. bacilli increased their loads significantly (p<0.05) during fermentation for 8-12 h and then remained constant. clostridia developed (p<0.05) subsequently to levels of 10(7) cfu/ml at 18 h, when the ph of the f ... | 2007 | 17300848 |
| influence of the protein environment on the redox potentials of flavodoxins from clostridium beijerinckii. | the flavin mononucleotide (fmn) quinones in flavodoxin have two characteristic redox potentials, namely, em(fmnh./fmnh-) for the one-electron reduction of the protonated fmn (e1) and em(fmn/fmnh.) for the proton-coupled one-electron reduction (e2). these redox potentials in native and mutant flavodoxins obtained from clostridium beijerinckii were calculated by considering the protonation states of all titratable sites as well as the energy contributed at the pka value of fmn during protonation a ... | 2007 | 17602164 |
| butanol production from wheat straw hydrolysate using clostridium beijerinckii. | in these studies, butanol (acetone butanol ethanol or abe) was produced from wheat straw hydrolysate (wsh) in batch cultures using clostridium beijerinckii p260. in control fermentation 48.9 g l(-1) glucose (initial sugar 62.0 g l(-1)) was used to produce 20.1 g l(-1) abe with a productivity and yield of 0.28 g l(-1 )h(-1) and 0.41, respectively. in a similar experiment where wsh (60.2 g l(-1) total sugars obtained from hydrolysis of 86 g l(-1) wheat straw) was used, the culture produced 25.0 g ... | 2007 | 17609986 |
| co-regulation of the nitrogen-assimilatory gene cluster in clostridium saccharobutylicum. | nitrogen assimilation is important during solvent production by clostridium saccharobutylicum ncp262, as acetone and butanol yields are significantly affected by the nitrogen source supplied. growth of this bacterium was dependent on the concentration of organic nitrogen supplied and the expression of the assimilatory enzymes, glutamine synthetase (gs) and glutamate synthase (gogat), was shown to be induced in nitrogen-limiting conditions. the regions flanking the gene encoding gs, glna, were is ... | 2007 | 17768251 |
| production of acetone butanol (ab) from liquefied corn starch, a commercial substrate, using clostridium beijerinckii coupled with product recovery by gas stripping. | a potential industrial substrate (liquefied corn starch; lcs) has been employed for successful acetone butanol ethanol (abe) production. fermentation of lcs (60 g l(-1)) in a batch process resulted in the production of 18.4 g l(-1) abe, comparable to glucose: yeast extract based medium (control experiment, 18.6 g l(-1) abe). a batch fermentation of lcs integrated with product recovery resulted in 92% utilization of sugars present in the feed. when abe was recovered by gas stripping (to relieve i ... | 2007 | 17926074 |
| engineered synthetic pathway for isopropanol production in escherichia coli. | a synthetic pathway was engineered in escherichia coli to produce isopropanol by expressing various combinations of genes from clostridium acetobutylicum atcc 824, e. coli k-12 mg1655, clostridium beijerinckii nrrl b593, and thermoanaerobacter brockii htd4. the strain with the combination of c. acetobutylicum thl (acetyl-coenzyme a [coa] acetyltransferase), e. coli atoad (acetoacetyl-coa transferase), c. acetobutylicum adc (acetoacetate decarboxylase), and c. beijerinckii adh (secondary alcohol ... | 2007 | 17933911 |
| fermentation of dried distillers' grains and solubles (ddgs) hydrolysates to solvents and value-added products by solventogenic clostridia. | pretreatment and hydrolysis of lignocellulosic biomass using either dilute acid, liquid hot water (lhw), or ammonium fiber expansion (afex) results in a complex mixture of sugars such as hexoses (glucose, galactose, mannose), and pentoses (xylose, arabinose). a detailed description of the utilization of representative mixed sugar streams (pentoses and hexoses) and their sugar preferences by the solventogenic clostridia (clostridium beijerinckii ba101, c. acetobutylicum 260, c. acetobutylicum 824 ... | 2008 | 17967532 |
| genetic features of circular bacteriocins produced by gram-positive bacteria. | this review highlights the main genetic features of circular bacteriocins, which require the co-ordinated expression of several genetic determinants. in general terms, it has been demonstrated that the expression of such structural genes must be combined with the activity of proteins involved in maturation (cleavage/circularization) and secretion outside the cell via different transporter systems, as well as multifaceted immunity mechanisms essential to ensuring the bacteria's self-protection ag ... | 2008 | 18034824 |
| butanol production by clostridium beijerinckii. part i: use of acid and enzyme hydrolyzed corn fiber. | fermentation of sulfuric acid treated corn fiber hydrolysate (sacfh) inhibited cell growth and butanol production (1.7+/-0.2g/l acetone butanol ethanol or abe) by clostridium beijerinckii ba101. treatment of sacfh with xad-4 resin removed some of the inhibitors resulting in the production of 9.3+/-0.5 g/l abe and a yield of 0.39+/-0.015. fermentation of enzyme treated corn fiber hydrolysate (etcfh) did not reveal any cell inhibition and resulted in the production of 8.6+/-1.0 g/l abe and used 24 ... | 2008 | 18061440 |
| influence of reduced electron shuttling compounds on biological h2 production in the fermentative pure culture clostridium beijerinckii. | several reports suggest that extracellular electron shuttles influence fermentative metabolism in a beneficial manner for bioremediation and biotechnology strategies. the focus of this research was to characterize the effects of reduced electron shuttling molecules on fermentative h(2) production. reduced electron shuttles may provide reducing equivalents to generate h(2), which influences alternate cellular processes. electron shuttling compounds cycle between reduced-oxidized states and influe ... | 2008 | 18167025 |
| redox potential difference between desulfovibrio vulgaris and clostridium beijerinckii flavodoxins. | the redox potential of the flavin mononucleotide (fmn) hydroquinones for one-electron reduction in the desulfovibrio vulgaris ( d. vulgaris) flavodoxin ( e sq/hq for fmnh (*)/fmnh (-)) was calculated using the crystal structure of the relevant hydroquinone form and compared to the results of the clostridium beijerinckii ( c. beijerinckii) flavodoxin. in d. vulgaris and c. beijerinckii flavodoxins, the protein side chain causes significant downshifts of 170 and 240 mv in e sq/hq, respectively. in ... | 2008 | 18355044 |
| continuos ibe fermentation by immobilized growing clostridium beijerinckii cells in a stirred-tank fermentor. | the potential of continuous isopropanol-butanol-ethanol (ibe) fermentation by ca-alginate-immobilized clostridium beijerinckii cells in a continuous stirred-tank reactor is investigated. a mathematical model is presented to describe steady-state reactor performance. it appeared to be possible to use the biocatalyst particles repeatedly for successive fermentations (at least three times for a total duration of two months). reactor productivity was 6-16 times higher than that of a batch fermentati ... | 1983 | 18548553 |
| experience with solvent production by clostridium beijerinckii in continuous culture. | 1983 | 18548731 | |
| chitinolytic activities of clostridium sp. jm2 isolated from stool of human administered per orally by chitosan. | the novel chitinolytic bacterium clostridium beijerinckii strain jm2 was isolated from the stool of healthy volunteers supplied daily per orally with 3 g of chitosan. the bacterium grown on colloidal chitin produced a complete array of chitinolytic enzymes. significant activities of endochitinase, exochitinase and chitosanase were excreted into the medium (301, 282 and 268 nkat/microg protein, respectively). the high cellular activity of n-acetyl-beta-glucosaminidase (nagase) and chitosanase wer ... | 2008 | 18661303 |
| transcriptional analysis of clostridium beijerinckii ncimb 8052 and the hyper-butanol-producing mutant ba101 during the shift from acidogenesis to solventogenesis. | clostridium beijerinckii is an anaerobic bacterium used for the fermentative production of acetone and butanol. the recent availability of genomic sequence information for c. beijerinckii ncimb 8052 has allowed for an examination of gene expression during the shift from acidogenesis to solventogenesis over the time course of a batch fermentation using a ca. 500-gene set dna microarray. the microarray was constructed using a collection of genes which are orthologs of members of gene families prev ... | 2008 | 18849451 |
| metabolic engineering of saccharomyces cerevisiae for the production of n-butanol. | abstract: background: increasing energy costs and environmental concerns have motivated engineering microbes for the production of "second generation" biofuels that have better properties than ethanol. results and conclusion: saccharomyces cerevisiae was engineered with an n-butanol biosynthetic pathway, in which isozymes from a number of different organisms (s. cerevisiae, escherichia coli, clostridium beijerinckii, and ralstonia eutropha) were substituted for the clostridial enzymes and their ... | 2008 | 19055772 |
| detoxification of model phenolic compounds in lignocellulosic hydrolysates with peroxidase for butanol production from clostridium beijerinckii. | in the present study, we investigated the peroxidase-catalyzed detoxification of model phenolic compounds and evaluated the inhibitory effects of the detoxified solution on butanol production by clostridium beijerinckii national collection of industrial and marine bacteria ltd. 8052. the six phenolic compounds, p-coumaric acid, ferulic acid, 4-hydroxybenzoic acid, vanillic acid, syringaldehyde, and vanillin, were selected as model fermentation inhibitors generated during pretreatment and hydroly ... | 2009 | 19300996 |
| fermentation of rice bran and defatted rice bran for butanol 5 production using clostridium beijerinckii ncimb 8052. | we examined butanol fermentation by clostridium beijerinckii ncimb 8052 using various hydrolyzates obtained from rice bran, which is one of the most abundant agricultural by-products in korea and japan. in order to increase the amount of fermentable sugars in the hydrolyzates of rice bran, various hydrolysis procedures were applied. eight different hydrolyzates were prepared using rice bran (rb) and defatted rice bran (drb) with enzyme or acid treatment or both. each hydrolyzate was evaluated in ... | 2009 | 19494696 |
| isolation of a new butanol-producing clostridium strain: high level of hemicellulosic activity and structure of solventogenesis genes of a new clostridium saccharobutylicum isolate. | new isolates of solventogenic bacteria exhibited high hemicellulolytic activity. they produced butanol and acetone with high selectivity for butanol (about 80% of butanol from the total solvent yield). their 16s rdna sequence was 99% identical to that of clostridium saccharobutylicum. the genes responsible for the last steps of solventogenesis and encoding crotonase, butyryl-coa dehydrogenase, electron-transport protein subunits a and b, 3-hydroxybutyryl-coa dehydrogenase, alcohol dehydrogenase, ... | 2009 | 19674858 |
| the clostron: mutagenesis in clostridium refined and streamlined. | the recent development of the clostron group ii intron directed mutagenesis tool for clostridium has advanced genetics in this genus, and here we present several significant improvements. we have shown how marker re-cycling can be used to construct strains with multiple mutations, demonstrated using flp/frt in clostridium acetobutylicum; tested the capacity of the system for the delivery of transgenes to the chromosome of clostridium sporogenes, which proved feasible for 1.0kbp transgenes in add ... | 2010 | 19891996 |
| comparison of different mixed cultures for bio-hydrogen production from ground wheat starch by combined dark and light fermentation. | composition of the mixed culture was varied in combined dark-light fermentation of wheat powder starch in order to improve hydrogen gas formation rate and yield. heat-treated anaerobic sludge and pure culture of clostridium beijerinckii (dsmz 791t) were combined with two different light fermentation bacteria of rhodobacter sphaeroides (rs-nrrl and rs-rv) in order to select a more suitable mixture resulting in high hydrogen yield and formation rate. a combination of the anaerobic sludge and rs-nr ... | 2010 | 20033469 |
| biochemical and structural properties of chimeras constructed by exchange of cofactor-binding domains in alcohol dehydrogenases from thermophilic and mesophilic microorganisms. | the cofactor-binding domains (residues 153-295) of the alcohol dehydrogenases from the thermophile thermoanaerobacter brockii (tbadh), the mesophilic bacterium clostridium beijerinckii (cbadh), and the protozoan parasite entamoeba histolytica (ehadh1) have been exchanged. three chimeras have been constructed. in the first chimera, the cofactor-binding domain of thermophilic tbadh was replaced with the cofactor-binding domain of its mesophilic counterpart cbadh [chimera chi21((tct))]. this domain ... | 2010 | 20102159 |
| functional expression of the thiolase gene thl from clostridium beijerinckii p260 in lactococcus lactis and lactobacillus buchneri. | the first step of the butanol pathway involves an acetyl-coa acetyltransferase (acoaat), which controls the key branching point from acetyl-coa to butanol. acoaat, also known as thiolase (ec 2.3.1.9), is encoded by the thl gene and catalyzes ligation of two acetyl-coa into acetoacetyl-coa. bioinformatics analyses suggest there are no thl in the genomes of lactic acid bacteria (lab), in this study we aimed to introduce the thl gene into selected lab strains and analyze the fermentation products. ... | 2010 | 20371307 |
| butanol production by clostridium beijerinckii atcc 55025 from wheat bran. | wheat bran, a by-product of the wheat milling industry, consists mainly of hemicellulose, starch and protein. in this study, the hydrolysate of wheat bran pretreated with dilute sulfuric acid was used as a substrate to produce abe (acetone, butanol and ethanol) using clostridium beijerinckii atcc 55025. the wheat bran hydrolysate contained 53.1 g/l total reducing sugars, including 21.3 g/l of glucose, 17.4 g/l of xylose and 10.6 g/l of arabinose. c. beijerinckii atcc 55025 can utilize hexose and ... | 2010 | 20393827 |
| the t box regulatory element controlling expression of the class i lysyl-trna synthetase of bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-trnaasn. | lysyl-trna synthetase (lysrs) is unique within the aminoacyl-trna synthetase family in that both class i (lysrs1) and class ii (lysrs2) enzymes exist. lysrs1 enzymes are found in archaebacteria and some eubacteria while all other organisms have lysrs2 enzymes. all sequenced strains of bacillus cereus (except ah820) and bacillus thuringiensis however encode both a class i and a class ii lysrs. the lysk gene (encoding lysrs1) of b. cereus strain 14579 has an associated t box element, the first rep ... | 2010 | 20649968 |
| clostridium chromiireducens sp. nov., a novel strain isolated from a cr(vi)-contaminated soil. | strain gcaf-1 is a cr(vi)-resistant, gram positive, spore-forming obligate anaerobe that was 2 isolated from a chromium-contaminated soil by its ability to reduce cr(vi) in low 3 concentrations, fe(iii), and the humic-acid analog aqds. a mixed acid fermentation resulting 4 in accumulation of acetate, butyrate and lactate is observed during growth of gcaf-1 on 5 glucose. morphological studies on this strain indicate the presence of peritrichous flagella, pili 6 and an s-layer. major cellular fatt ... | 2010 | 21148674 |
| large number of phosphotransferase genes in the clostridium beijerinckii ncimb 8052 genome and the study on their evolution. | clostridium beijerinckii is a valuable bacteria species which has the ability of abe (acetone, butanol and ethanol) production. it has been shown that phosphotransferase (pts) is an important and common system for both carbohydrate uptake and phosphorylation in bacteria, but detailed study of the system, especially its fructose/mannose/sorbose family is scant. | 2010 | 21172059 |
| d-2,3-butanediol production due to heterologous expression of an acetoin reductase in clostridium acetobutylicum. | acetoin reductase (acr) catalyzes the conversion of acetoin to 2,3-butanediol. under certain conditions, clostridium acetobutylicum atcc 824 (and strains derived from it) generates both d- and l-stereoisomers of acetoin, but because of the absence of an acr enzyme, it does not produce 2,3-butanediol. a gene encoding acr from clostridium beijerinckii ncimb 8052 was functionally expressed in c. acetobutylicum under the control of two strong promoters, the constitutive thl promoter and the late exp ... | 2011 | 21335380 |
| continuous production of 1,3-propanediol using raw glycerol with immobilized clostridium beijerinckii nrrl b-593 in comparison to suspended culture. | the continuous production of 1,3-propanediol (1,3-pdo) was investigated with clostridium beijerinckii nrrl b-593 using raw glycerol without purification obtained from a biodiesel production process. ceramic rings and pumice stones were used for cell immobilization in a packed-bed bioreactor. for comparison purpose, a control bioreactor with suspended culture was also run. the effect of hydraulic retention time (hrt) on the production of 1,3-pdo in both immobilized and suspended bioreactors were ... | 2011 | 21336641 |
| bioproduction of butanol in bioreactors: new insights from simultaneous in situ butanol recovery to eliminate product toxicity. | simultaneous acetone butanol ethanol (abe) fermentation by clostridium beijerinckii p260 and in situ product recovery was investigated using a vacuum process operated in two modes: continuous and intermittent. integrated batch fermentations and abe recovery were conducted at 37 °c using a 14-l bioreactor (7.0 l fermentation volume) containing initial substrate (glucose) concentration of 60 g/l. the bioreactor was connected in series with a condensation system and vacuum pump. vacuum was applied ... | 2011 | 21370232 |
| hydrogen production by the newly isolated clostridium beijerinckii rzf-1108. | a fermentative hydrogen-producing strain, rzf-1108, was isolated from a biohydrogen reactor, and identified as clostridium beijerinckii on the basis of the 16s rrna gene analysis and physiobiochemical characteristics. the effects of culture conditions on hydrogen production by c. beijerinckii rzf-1108 were investigated in batch cultures. the hydrogen production and growth of strain rzf-1108 were highly dependent on temperature, initial ph and substrate concentration. yeast extract was a favorabl ... | 2011 | 21421301 |
| improved efficiency of separate hexose and pentose fermentation from steam-exploded corn stalk for butanol production using clostridium beijerinckii. | water extract of steam-exploded corn stalk (secs) was detoxified and used as feed for acetone-butanol-ethanol (abe) fermentation using clostridium beijerinckii. utilization of water extract improved the total abe yield (g abe/g dry secs). separated fermentation showed higher fermentability (0.078 g abe/g dry secs) over typical fermentation (0.058 g abe/g dry secs). furthermore, the final abe yields (g abe/g utilized sugar) from water extract neutralized by ca(oh)(2), naoh, and na(2)so(3) were 0. ... | 2011 | 21424838 |
| butanol production from the effluent of hydrogen fermentation. | the purpose of the study was to recover butanol from the effluent of the hydrogen-producing bioreactor containing acetate, butyrate, and carbohydrate. the butanol production by clostridium beijerinckii nrrl b592 was evaluated under both unsterilized and sterilized conditions for examining the potential of butanol production for the practical application. sucrose of 10 g/l and butyrate of 2 g/l coupled with acetate buffer were used to mimic the effluent. sucrose was completely consumed in the bot ... | 2011 | 21436562 |
| acetone production in solventogenic clostridium species: new insights from non-enzymatic decarboxylation of acetoacetate. | development of a butanologenic strain with high selectivity for butanol production is often proposed as a possible route for improving the economics of biobutanol production by solventogenic clostridium species. the acetoacetate decarboxylase (aadc) gene encoding acetoacetate decarboxylase (aadc), which catalyzes the decarboxylation of acetoacetate into acetone and co(2), was successfully disrupted by homologous recombination in solventogenic clostridium beijerinckii ncimb 8052 to generate an aa ... | 2011 | 21533580 |
| continuous production of isopropanol and butanol using clostridium beijerinckii dsm 6423. | clostridium beijerinckii dsm 6423 was studied using different continuous production methods to give maximum and stable production of isopropanol and n-butanol. in a single-stage continuous culture, when wood pulp was added as a cell holding material, we could increase the solvent productivity from 0.47 to 5.52 g l(-1) h(-1) with the yield of 54% from glucose. the overall solvent concentration of 7.51 g l(-1) (39.4% isopropanol and 60.6% n-butanol) with the maximum solvent productivity of 0.84 g ... | 2011 | 21573939 |
| nutritional requirements of solventogenic clostridia growing under butanol stress and co-utilization of d-glucose/d-xylose. a meta-analysis and a functional validation. | recent advances in systems biology, omics, and computational studies allow us to carry out data mining for improving biofuel production bioprocesses. of particular interest are bioprocesses that center on microbial capabilities to biotransform both the hexose and the pentose fractions present in crop residues. this called for a systematic exploration of media components to obtain higher density cultures and more productive fermentation operations than are currently found. by using a meta-analysi ... | 2011 | 21602379 |
| butanol production from crystalline cellulose by co-cultured clostridium thermocellum and clostridium saccharoperbutylacetonicum n1-4. | we investigated butanol production from crystalline cellulose by co-cultured cellulolytic clostridium thermocellum and the butanol-producing strain, c. saccharoperbutylacetonicum (strain n1-4). butanol was produced from avicel cellulose after incubation with c. thermocellum for at least 24 h at 60°c before adding strain n1-4. butanol produced by strain n1-4 on 4% avicel cellulose peaked (7.9 g/l) after 9 days of incubation at 30°c and acetone was undetectable in this co-culture system. less buta ... | 2011 | 21764954 |
| clostridium beijerinckii mutant with high inhibitor tolerance obtained by low-energy ion implantation. | clostridium beijerinckii mutant strain ib4, which has a high level of inhibitor tolerance, was screened by low-energy ion implantation and used for butanol fermentation from a non-detoxified hemicellulosic hydrolysate of corn fiber treated with dilute sulfuric acid (sahhc). evaluation of toxicity showed c. beijerinckii ib4 had a higher level of tolerance than parent strain c. beijerinckii ncimb 8052 for five out of six phenolic compounds tested (the exception was vanillin). using glucose as carb ... | 2011 | 21789489 |
| clostridium beijerinckii mutant obtained by atmospheric pressure glow discharge producing high proportions of butanol and solvent yields. | with 30-ág glucose/l as carbon source, clostridium beijerinckii art124, a mutant created by atmospheric pressure glow discharge, produced 13.7-ág total solvent/l (containing 3.1-ág acetone/l, 10.4-ág butanol/l and 0.2-ág ethanol/l) in 72-áh. the mutant could also use sucrose or xylose or a mixture of glucose/xylose/arabinose with nearly equal yields. | 2011 | 21833546 |
| metabolic network reconstruction and genome-scale model of butanol-producing strain clostridium beijerinckii ncimb 8052. | solventogenic clostridia offer a sustainable alternative to petroleum-based production of butanol--an important chemical feedstock and potential fuel additive or replacement. c. beijerinckii is an attractive microorganism for strain design to improve butanol production because it (i) naturally produces the highest recorded butanol concentrations as a byproduct of fermentation; and (ii) can co-ferment pentose and hexose sugars (the primary products from lignocellulosic hydrolysis). interrogating ... | 2011 | 21846360 |
| outgrowth inhibition of clostridium beijerinckii spores by a bacteriocin-producing lactic culture in ovine milk cheese. | in the manufacture of model cheeses, ovine milk was deliberately contaminated with spores of clostridium beijerinckii inia 63, a wild isolate from manchego cheese with late blowing defect, and inoculated with nisin- and lacticin 481-producing lactococcus lactis subsp. lactis inia 415 as starter, to test its potential to prevent the late blowing defect, or with l. lactis subsp. lactis inia 415-2, a spontaneous mutant not producing bacteriocins. cheeses made individually with the lactococcal strai ... | 2011 | 21849216 |
| Optimization of butanol production from tropical maize stalk juice by fermentation with Clostridium beijerinckii NCIMB 8052. | Mixed sugars from tropical maize stalk juice were used to carry out butanol fermentation with Clostridium beijerinckii NCIMB 8052. Batch experiments employing central composite design (CCD) and response surface methodology (RSM) optimization were performed to evaluate effects of three factors, i.e. pH, initial total sugar concentration, and agitation rate on butanol production. Optimum conditions of pH 6.7, sugar concentration 42.2g/L and agitation rate 48 rpm were predicted, under which a maxim ... | 2011 | 21893411 |
| anthrahydroquinone-2,6,-disulfonate (ah2qds) increases hydrogen molar yield and xylose utilization in growing cultures of clostridium beijerinckii. | h(2) production and xylose utilization were investigated using the fermentative culture clostridium beijerinckii ncimb 8052. adding anthrahydroquinone-2,6-disulfonate (ah(2)qds) increased the extent of xylose utilization by 56% and hydrogen molar yield by 24-37%. enhanced hydrogen molar yield correlated with increased xylose utilization and increases in the acetate/butyrate product ratio. an electron balance indicated that ah(2)qds shifted the electrons from the butyric acid pathway (nadh-depend ... | 2011 | 21947605 |
| single-nucleotide resolution analysis of the transcriptome structure of clostridium beijerinckii ncimb 8052 using rna-seq. | clostridium beijerinckii is an important solvent producing microorganism. the genome of c. beijerinckii ncimb 8052 has recently been sequenced. although transcriptome structure is important in order to reveal the functional and regulatory architecture of the genome, the physical structure of transcriptome for this strain, such as the operon linkages and transcript boundaries are not well understood. | 2011 | 21962126 |
| Metabolic Engineering of Clostridium acetobutylicum ATCC 824 for Isopropanol-Butanol-Ethanol Fermentation. | Clostridium acetobutylicum naturally produces acetone as well as butanol and ethanol. Since acetone cannot be used as a biofuel, its production needs to be minimized or suppressed by cell or bioreactor engineering. Thus, there have been attempts to disrupt or inactivate the acetone formation pathway. Here we present another approach, namely converting acetone to isopropanol by metabolic engineering. Since isopropanol can be used as a fuel additive, the mixture of isopropanol, butanol, and ethano ... | 2011 | 22210214 |
| genome-wide dynamic transcriptional profiling in clostridium beijerinckii ncimb 8052 using single-nucleotide resolution rna-seq. | clostridium beijerinckii is a prominent solvent-producing microbe that has great potential for biofuel and chemical industries. although transcriptional analysis is essential to understand gene functions and regulation and thus elucidate proper strategies for further strain improvement, limited information is available on the genome-wide transcriptional analysis for c. beijerinckii. | 2012 | 22433311 |
| the antimicrobial action of chitosan, low molar mass chitosan, and chitooligosaccharides on human colonic bacteria. | antibacterial effect of chitooligosaccharides (cos) and low molar mass chitosans (lmwc) is considered as one of the most important characteristics of chitosan (cs) hydrolysates. here, we show the in vitro effect of different cos, lmwc, and cs on representative anaerobic bacteria isolated from human colon as a possibility of targeting modification of colonic microflora composition by supplementation of dietary cs products by humans. specific growth rate of seven selected nonpathogenic anaerobic b ... | 2012 | 22528310 |
| metabolic engineering of d-xylose pathway in clostridium beijerinckii to optimize solvent production from xylose mother liquid. | clostridium beijerinckii is an attractive butanol-producing microbe for its advantage in co-fermenting hexose and pentose sugars. however, this clostridium strain exhibits undesired efficiency in utilizing d-xylose, one of the major building blocks contained in lignocellulosic materials. here, we reported a useful metabolic engineering strategy to improve d-xylose consumption by c. beijerinckii. gene cbei2385, encoding a putative d-xylose repressor xylr, was first disrupted in the c. beijerincki ... | 2012 | 22677452 |
| microbial production of a biofuel (acetone-butanol-ethanol) in a continuous bioreactor: impact of bleed and simultaneous product removal. | acetone butanol ethanol (abe) was produced in an integrated continuous one-stage fermentation and gas stripping product recovery system using clostridium beijerinckii ba101 and fermentation gases (co(2) and h(2)). in this system, the bioreactor was fed with a concentrated sugar solution (250-500 g l(-1) glucose). the bioreactor was bled semi-continuously to avoid accumulation of inhibitory chemicals and products. the continuous system was operated for 504 h (21 days) after which the fermentation ... | 2013 | 22729675 |
| butanol production from corncob residue using clostridium beijerinckii ncimb 8052. | to determine whether corncob residue (ccr) could be a good substrate for butanol production. | 2012 | 22738279 |
| introducing a single secondary alcohol dehydrogenase into butanol-tolerant clostridium acetobutylicum rh8 switches abe fermentation to high level ibe fermentation. | 2012 | 22742819 | |
| lipid diversity among botulinum neurotoxin-producing clostridia. | clostridium botulinum has been classified into four groupings (groups i to iv) based on physiological characteristics and 16s rrna sequencing. we have examined the lipid compositions of 11 representative strains of c. botulinum and a strain of clostridium sporogenes by 2d-tlc and by ms. all strains contained phosphatidylglycerol (pg), cardiolipin (cl) and phosphatidylethanolamine (pe) in both the all-acyl and the alk-1'-enyl (plasmalogen) forms. five strains in proteolytic group i, which are rel ... | 2012 | 22837302 |
| identification of clostridium beijerinckii, cl. butyricum, cl. sporogenes, cl. tyrobutyricum isolated from silage, raw milk and hard cheese by a multiplex pcr assay. | late blowing, caused by the outgrowth of clostridial spores present in raw milk and originating from silage, can create considerable product loss, especially in the production of hard and semi-hard cheeses. the conventional method for the isolation of clostridium spp. from cheeses with late-blowing symptoms is very complicated and the identification of isolates is problematic. the aim of this work was the development of a multiplex pcr method for the detection of the main dairy-related clostridi ... | 2012 | 22850580 |
| use of the fluorescent probe laurdan to label and measure inner membrane fluidity of endospores of clostridium spp. | a method for measuring the fluidity of inner membranes of populations of endospores of clostridium spp. with a fluorescent dye was developed. cells of clostridium beijerinckii atcc 8260 and clostridium sporogenes atcc 7955 were allowed to sporulate in the presence of 6-dodecanoyl-2-dimethylaminonaphthalene (laurdan) on a soil-based media. labeling of endospores with laurdan did not affect endospore viability. removal of the outer membranes of endospores was done using a chemical treatment and co ... | 2012 | 22884687 |
| interactions between clostridium beijerinckii and geobacter metallireducens in co-culture fermentation with anthrahydroquinone-2, 6-disulfonate (ah2qds) for enhanced biohydrogen production from xylose. | to enhance biohydrogen production, clostridium beijerinckii was co-cultured with geobacter metallireducens in the presence of the reduced extracellular electron shuttle anthrahydroquinone-2, 6-disulfonate (ah(2)qds). in the co-culture system, increases of up to 52.3% for maximum cumulative hydrogen production, 38.4% for specific hydrogen production rate, 15.4% for substrate utilization rate, 39.0% for substrate utilization extent, and 34.8% for hydrogen molar yield in co-culture fermentation wer ... | 2013 | 22886601 |
| simultaneous production of isopropanol, butanol, ethanol and 2,3-butanediol by clostridium acetobutylicum atcc 824 engineered strains. | isopropanol represents a widely-used commercial alcohol which is currently produced from petroleum. in nature, isopropanol is excreted by some strains of clostridium beijerinckii, simultaneously with butanol and ethanol during the isopropanol butanol ethanol (ibe) fermentation. in order to increase isopropanol production, the gene encoding the secondary-alcohol dehydrogenase enzyme from c. beijerinckii nrrl b593 (adh) which catalyzes the reduction of acetone to isopropanol, was cloned into the a ... | 2012 | 22909015 |
| draft genome sequence of butanol-acetone-producing clostridium beijerinckii strain g117. | a recently discovered wild-type strain, clostridium beijerinckii g117, is unique in producing butanol and acetone but negligible amounts of ethanol, unlike previously identified acetone-butanol-ethanol (abe)-generating microbes. here we report the draft genome sequence of strain g117 (5,806,675 bp; gc content, 29.7%) and the novel findings obtained from its genome annotations. | 2012 | 22965093 |
| butanol production from hemicellulosic hydrolysate of corn fiber by a clostridium beijerinckii mutant with high inhibitor-tolerance. | a clostridium beijerinckii mutant rt66 with considerable inhibitor-tolerance obtained by continuous culture was used for butanol production from non-detoxified hemicellulosic hydrolysate of corn fiber treated with dilute sulfuric acid (sahhc). in fed-batch fermentation, 1.8l of diluted sahhc containing 10 g/l of reducing sugar was provided during the acidogenic phase and 0.2l of concentrated sahhc containing 300 g/l of reducing sugar was provided during the solventogenic phase. the mutant produc ... | 2013 | 22985825 |
| use of proteomic analysis to elucidate the role of calcium in acetone-butanol-ethanol fermentation by clostridium beijerinckii ncimb 8052. | calcium carbonate increases growth, substrate utilization, and acetone-butanol-ethanol (abe) fermentation by clostridium beijerinckii ncimb 8052. toward an understanding of the basis for these pleiotropic effects, we profiled changes in the c. beijerinckii ncimb 8052 proteome that occur in response to the addition of caco(3). we observed increases in the levels of different heat shock proteins (grpe and dnak), sugar transporters, and proteins involved in dna synthesis, repair, recombination, and ... | 2013 | 23104411 |
| wood pulp as an immobilization matrix for the continuous production of isopropanol and butanol. | the study was focused on developing a continuous method to produce an alcohol mixture suitable to be used as a gasoline supplement. the immobilized column reactor with wood pulp fibers was successfully used for the continuous production of butanol and isopropanol using clostridium beijerinckii dsm 6423. a sugar mixture (glucose, mannose, galactose, arabinose and xylose) representing lignocellulose hydrolysate was used as a substrate for the production of solvents. the effect of dilution rate on ... | 2013 | 23184175 |
| production of acetone, butanol, and ethanol from biomass of the green seaweed ulva lactuca. | green seaweed ulva lactuca harvested from the north sea near zeeland (the netherlands) was characterized as feedstock for acetone, ethanol and ethanol fermentation. solubilization of over 90% of sugars was achieved by hot-water treatment followed by hydrolysis using commercial cellulases. a hydrolysate was used for the production of acetone, butanol and ethanol (abe) by clostridium acetobutylicum and clostridium beijerinckii. hydrolysate-based media were fermentable without nutrient supplementat ... | 2013 | 23201525 |
| butanol production from acid hydrolyzed corn fiber with clostridium beijerinckii mutant. | sulfuric acid treated corn fiber hydrolysate (sacfh) inhibited cell growth and the production of butanol (4.7±0.2 g/l) by clostridium beijerinckii ib4 in p2 medium. optimal medium components were determined using fractional factorial design. nh4hco3, feso4·7h2o and caco3 were demonstrated to be significant components in the production of butanol. the box-behnken design and a corresponding quadratic model were used to predict medium components (nh4hco3 1.96 g/l, feso4·7h2o 0.26 g/l and caco3 3.15 ... | 2013 | 23305897 |
| isolation, characterization and evaluation of hyper 2-propanol producing bacteria from singapore environment. | three hyper 2-propanol producing strains were isolated from singapore environment using an enrichment step and a high through-put screening step. the analysis of the amplified 16s rdna revealed that the isolates belonged to clostridium species and they were named as clostridium sp. bt10-1, clostridium sp. m10-1 and clostridium sp. pu31-4. at 1 l scale, the 2-propanol titer of these positive strains was 1.6-2.1 times of that of clostridium beijerinckii nrrl b593, which is so far the most efficien ... | 2013 | 23361972 |
| effects of nisin and reutericyclin on resistance of endospores of clostridium spp. to heat and high pressure. | the effects of high pressure, temperature, and antimicrobial compounds on endospores of clostridium spp. were examined. minimal inhibitory concentrations (mic) of nisin and reutericyclin were determined for vegetative cells and endospores of clostridium sporogenes atcc 7955, clostridium beijerinckii atcc 8260, and clostridium difficile 3195. endospores of c. sporogenes atcc 7955 and c. beijerinckii atcc 8260 were exposed to 90 °c and 90 °c/600 mpa in the presence of 16 mg l(-1) nisin or 6.4 mg l ... | 2012 | 23498177 |
| "in situ" removal of isopropanol, butanol and ethanol from fermentation broth by gas stripping. | in this study, the removal of ibe from aqueous solutions by gas stripping has been characterized. the effect of one or more components in the solution on the kinetics of the separation has been studied, both at 37°c and at 70°c. gas stripping has been applied to batch, repeated batch and continuous cultures of clostridium beijerinckii grown on a glucose/xylose mixed sugar substrate mimicking lignocellulosic hydrolysates, with the aim of finding optimal conditions for a stable ibe-producing cultu ... | 2013 | 23584415 |
| acetone, butanol, and ethanol production from cane molasses using clostridium beijerinckii mutant obtained by combined low-energy ion beam implantation and n-methyl-n-nitro-n-nitrosoguanidine induction. | in order to obtain mutant strains showing higher solvent tolerance and butanol production than those of wild-type strains, the butanol-producing strain clostridium beijerinckii l175 was subjected to mutagenesis using a combined method of low-energy ion beam implantation and n-methyl-n-nitro-n-nitrosoguanidine induction. with this effort, mutant strain mut3 was isolated. when it was used for butanol fermentation in p2 medium, the production of butanol was 15.8±0.7 g/l 46% higher than the wild-typ ... | 2013 | 23587827 |
| metabolic engineering of clostridium acetobutylicum for the enhanced production of isopropanol-butanol-ethanol fuel mixture. | butanol is considered as a superior biofuel, which is conventionally produced by clostridial acetone-butanol-ethanol (abe) fermentation. among abe, only butanol and ethanol can be used as fuel alternatives. coproduction of acetone thus causes lower yield of fuel alcohols. thus, this study aimed at developing an improved clostridium acetobutylicum strain possessing enhanced fuel alcohol production capability. for this, we previously developed a hyper abe producing bkm19 strain was further enginee ... | 2013 | 23606675 |
| transcriptional analysis of clostridium beijerinckii ncimb 8052 to elucidate role of furfural stress during acetone butanol ethanol fermentation. | furfural is the prevalent microbial inhibitor generated during pretreatment and hydrolysis of lignocellulose biomass to monomeric sugars, but the response of acetone butanol ethanol (abe) producing clostridium beijerinckii ncimb 8052 to this compound at the molecular level is unknown. to discern the effect of furfural on c. beijerinckii and to gain insight into molecular mechanisms of action and detoxification, physiological changes of furfural-stressed cultures during acetone butanol ethanol (a ... | 2013 | 23642190 |
| metabolic engineering of candida utilis for isopropanol production. | a genetically-engineered strain of the yeast candida utilis harboring genes encoding (1) an acetoacetyl-coa transferase from clostridium acetobutylicum atcc 824, (2) an acetoacetate decarboxylase, and (3) a primary-secondary alcohol dehydrogenase derived from clostridium beijerinckii nrrl b593 produced up to 0.21 g/l of isopropanol. because the engineered strain accumulated acetate, isopropanol titer was improved to 1.2 g/l under neutralized fermentation conditions. optimization of isopropanol p ... | 2013 | 23674152 |
| acetone-butanol-ethanol (abe) production in fermentation of enzymatically hydrolyzed cassava flour by clostridium beijerinckii ba101 and solvent separation. | cassava constitutes an abundant substrate in tropical regions. the production of butanol in abe fermentation by clostridium beijerinckii ba101 using cassava flour (cf) was scaled-up to bioreactor level (5 l). optimized fermentation conditions were applied; that is, 40℃, 60 g/l cf, and enzymatic pretreatment of the substrate. the batch fermentation profile presented an acidogenic phase for the first 24 h and a solventogenic phase afterwards. an average of 37.01 g/l abe was produced after 83 h, wi ... | 2013 | 23727799 |
| enhanced butanol production by coculture of clostridium beijerinckii and clostridium tyrobutyricum. | cocultures of clostridium beijerinckii and clostridium tyrobutyricum in free-cell and immobilized-cell fermentation modes were investigated as a means of enhancing butanol production. the immobilized fermentation was performed in a fibrous-bed bioreactor (fbb). the results demonstrated that two-strain coculture significantly enhanced butanol production, yield and volumetric productivity compared with those in pure culture with or without butyric acid. further, continuous immobilized-cell cocultu ... | 2013 | 23819976 |
| butanol production from wood pulping hydrolysate in an integrated fermentation-gas stripping process. | wood pulping hydrolysate (wph) containing mainly xylose and glucose as a potential substrate for acetone-butanol-ethanol (abe) fermentation was studied. due to the inhibitors present in the hydrolysate, several dilution levels and detoxification treatments, including overliming, activated charcoal adsorption, and resin adsorption, were evaluated for their effectiveness in relieving the inhibition on fermentation. detoxification using resin and evaporation was found to be the most effective metho ... | 2013 | 23827441 |
| evaluation of recycling the effluent of hydrogen fermentation for biobutanol production: kinetic study with butyrate and sucrose concentrations. | butyrate in the effluent of hydrogen-producing bioreactor is a potential feed for biobutanol production. for recycling butyrate, this study investigated the kinetics of biobutanol production by clostridium beijerinckii nrrl b592 from different paired concentrations of butyrate and sucrose in a series of batch reactors. results show that the lag time of butanol production increased with higher concentration of either sucrose or butyrate. in regression analyses, the maximum specific butanol produc ... | 2013 | 23866171 |
| development of a gene knockout system using mobile group ii introns (targetron) and genetic disruption of acid production pathways in clostridium beijerinckii. | clostridium beijerinckii is a well-known solvent-producing microorganism with great potential for biofuel and biochemical production. to better understand and improve the biochemical pathway to solvents, the development of genetic tools for engineering c. beijerinckii is highly desired. based on mobile group ii intron technology, a targetron gene knockout system was developed for c. beijerinckii in this study. this system was successfully employed to disrupt acid production pathways in c. beijer ... | 2013 | 23872562 |
| felled oil palm trunk as a renewable source for biobutanol production by clostridium spp. | this study aimed to convert felled oil palm trunk to biobutanol by clostridium spp. for efficient utilization of oil palm trunk, it was separated into sap and trunk fiber. the sap was used directly while the trunk fiber was hydrolyzed to fermentable sugars before use. among five clostridia strains screened, clostridium acetobutylicum dsm 1731 was the most suitable strain for butanol production from the sap without any supplementation of nutrients. it produced the highest amount of butanol (14.4 ... | 2013 | 23933028 |
| lignocellulosic hydrolysates and extracellular electron shuttles for h2 production using co-culture fermentation with clostridium beijerinckii and geobacter metallireducens. | a co-culture of clostridium beijerinckii and geobacter metallireducens with ah2qds produced hydrogen from lignocellulosic hydrolysates (biomass of miscanthus prepared by hydrothermal treatment with dilute acids). this co-culture system enhanced hydrogen production from lignocellulosic hydrolysates by improving substrate utilization and diminishing acetate accumulation, despite the presence of fermentation inhibitors in the hydrolysates. the improvements were greater for xylose-rich hydrolysates. ... | 2013 | 23994308 |
| dual substrate specificity of an n-acetylglucosamine phosphotransferase system in clostridium beijerinckii. | the solventogenic clostridia have a considerable capacity to ferment carbohydrate substrates with the production of acetone and butanol, making them attractive organisms for the conversion of waste materials to valuable products. in common with other anaerobes, the clostridia show a marked dependence on the phosphoenolpyruvate (pep)-dependent phosphotransferase system (pts) to accumulate sugars and sugar derivatives. in this study, we demonstrate that extracts of clostridium beijerinckii grown o ... | 2013 | 23995920 |
| direct conversion of sugars and organic acids to biobutanol by non-growing cells of clostridium spp. incubated in a nitrogen-free medium. | several clostridium spp. were incubated in a nitrogen-free medium (non-growth medium) containing only butyric acid as a sole precursor for performing butanol production by non-growing cells. non-growing cells of clostridium spp., especially clostridium beijerinckii tistr 1461, could convert butyric acid to butanol via their sole solventogenic activity. this activity was further enhanced in the presence of glucose as a co-substrate. in addition to glucose, other monosaccharides (i.e., galactose a ... | 2013 | 23996124 |
| comparative phenotypic analysis and genome sequence of clostridium beijerinckii sa-1, an offspring of ncimb 8052. | production of butanol by solventogenic clostridia is controlled through metabolic regulation of the carbon flow and limited by its toxic effects. to overcome cell sensitivity to solvents, stress-directed evolution methodology was used three decades ago on clostridium beijerinckii ncimb 8052 that spawned the sa-1 strain. here, we evaluated sa-1 solventogenic capabilities when growing on a previously validated medium containing, as carbon- and energy-limiting substrates, sucrose and the products o ... | 2013 | 24068240 |
| engineering a synthetic pathway in cyanobacteria for isopropanol production directly from carbon dioxide and light. | production of alternate fuels or chemicals directly from solar energy and carbon dioxide using engineered cyanobacteria is an attractive method to reduce petroleum dependency and minimize carbon emissions. here, we constructed a synthetic pathway composed of acetyl-coa acetyl transferase (encoded by thl), acetoacetyl-coa transferase (encoded by atoad), acetoacetate decarboxylase (encoded by adc) and secondary alcohol dehydrogenase (encoded by adh) in synechococcus elongatus strain pcc 7942 to pr ... | 2013 | 24076145 |
| use of fluorescent staining and flow cytometry for monitoring physiological changes in solventogenic clostridia. | physiological changes in populations of clostridium beijerinckii and clostridium tetanomorphum were monitored by fluorescence staining and flow cytometry. to estimate the number of metabolically active cells in exponential growth, a combination of the dyes propidium iodide and carboxy fluorescein diacetate appeared to be a good choice for both species. during stationary phase, these stains did not reflect physiological changes sufficiently and therefore additional labeling with bis-(1,3-dibutylb ... | 2014 | 24211310 |
| time-resolved tryptophan fluorescence in flavodoxins. | the time-resolved fluorescence characteristics of tryptophan in flavodoxins isolated from the bacteriadesulfovibrio gigas, desulfovibrio vulgaris, clostridium beijerinckii, andmegasphaera elsdenii were examined. the fluorescence decays were recorded using pulsed synchrotron radiation as the excitation source and time-correlated single-photon counting in detection. the results were analyzed as lifetime distributions using the maximum entropy method. comparison of the fluorescence decays of normal ... | 1995 | 24226911 |
| effects of supplementary butyrate on butanol production and the metabolic switch in clostridium beijerinckii ncimb 8052: genome-wide transcriptional analysis with rna-seq. | butanol (n-butanol) has high values as a promising fuel source and chemical feedstock. biobutanol is usually produced by the solventogenic clostridia through a typical biphasic (acidogenesis and solventogenesis phases) acetone-butanol-ethanol (abe) fermentation process. it is well known that the acids produced in the acidogenic phase are significant and play important roles in the switch to solventogenesis. however, the mechanism that triggers the metabolic switch is still not clear. | 2013 | 24229082 |
| selection of clostridium spp. in biological sand filters neutralizing synthetic acid mine drainage. | in this study, three biological sand filter (bsf) were contaminated with a synthetic iron- [1500 mg l⁻¹ fe(ii), 500 mg l⁻¹ fe(iii)] and sulphate-rich (6000 mg l⁻¹ so₄²⁻) acid mine drainage (amd) (ph = 2), for 24 days, to assess the remediation capacity and the evolution of autochthonous bacterial communities (monitored by t-rflp and 16s rrna gene clone libraries). to stimulate bsf bioremediation involving sulphate-reducing bacteria, a readily degradable carbon source (glucose, 8000 mg l⁻¹) was i ... | 2014 | 24251832 |