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[evidence for a bacteriocin in erwinia uredovora]. 197664197
characterization of a bacteriocin produced by erwinia uredovora [proceedings]. 197993940
expression in escherichia coli, purification, and reactivation of the recombinant erwinia uredovora phytoene desaturase.a plasmid has been constructed by cloning the complete crti gene encoding phytoene desaturase from erwinia uredovora behind the lac z promoter of puc18 resulting in a reading frame for the full polypeptide with additional 9 amino acids at the n terminus. this plasmid mediated the overexpression of phytoene desaturase in transformed escherichia coli. the overexpressed enzyme was sequestrated into inclusion bodies requiring urea treatment for solubilization. purification to homogeneity was subsequ ...19921400305
molecular cloning and expression in escherichia coli of a cyanobacterial gene coding for phytoene synthase, a carotenoid biosynthesis enzyme.the first committed step in the biosynthetic pathway of carotenoids in plants and algae is the conversion of geranylgeranyl pyrophosphate (ggpp) to prephytoene pyrophosphate (pppp), which is converted to phytoene. we have cloned the gene pys that encodes the enzyme phytoene synthase in the cyanobacterium synechococcus pcc7942. the co-expression of pys in cells of escherichia coli together with the gene crte from erwinia uredovora, which encodes geranylgeranyl pyrophosphate synthase, resulted in ...19921537409
functional complementation in escherichia coli of different phytoene desaturase genes and analysis of accumulated carotenes.three different phytoene desaturase genes, from rhodobacter capsulatus, erwinia uredovora, and synechococcus pcc 7942, have been functionally complemented with a gene construct from e. uredovora which encodes all enzymes responsible for formation of 15-cis phytoene in escherichia coli. as indicated by the contrasting reaction products detected in the pigmented e. coli cells after co-transformation, a wide functional diversity of these three different types of phytoene desaturases can be conclude ...19911817513
production of beta-carotene in zymomonas mobilis and agrobacterium tumefaciens by introduction of the biosynthesis genes from erwinia uredovora.the erwinia uredovora crtb, crte, crti, and crty genes required for beta-carotene biosynthesis were introduced by conjugal transfer into an ethanol-producing bacterium, zymomonas mobilis, and a phytopathogenic bacterium, agrobacterium tumefaciens, in which no carotenoid is synthesized. the transconjugants of z. mobilis and a. tumefaciens carrying these genes appeared as yellow colonies and produced 220 and 350 micrograms of beta-carotene per g of dry weight, respectively, in the stationary phase ...19911872613
elucidation of the erwinia uredovora carotenoid biosynthetic pathway by functional analysis of gene products expressed in escherichia coli.the most important function of carotenoid pigments, especially beta-carotene in higher plants, is to protect organisms against photooxidative damage (g. britton, in t. w. goodwin, ed., plant pigments--1988, 1988; n. i. krinsky, in o. isler, h. gutmann, and u. solms, ed., carotenoids--1971, 1971). beta-carotene also functions as a precursor of vitamin a in mammals (g. a. j. pitt, in i. osler, h. gutmann, and u. solms, ed., carotenoids--1971, 1971). the enzymes and genes which mediate the biosynth ...19902254247
an ice nucleation active gene of erwinia ananas. sequence similarity to those of pseudomonas species and regions required for ice nucleation activity.the ice nucleation active gene, inaa, of erwinia ananas in-10 has been sequenced. this gene encodes a protein composed of 1322 amino acid residues. the inaa protein contains a 1120-residue segment consisting of 70 repeats of closely related 16 amino acid motifs (r-domain), which is flanked by n- and c-terminal sequences (n- and c-domains, respectively). its primary structure is similar to, but not identical with, those of pseudomonas inaw and inaz gene products. by truncating the inaa gene to va ...19892599095
characterization of xylitol-utilizing mutants of erwinia uredovora.of the four pentitols ribitol, xylitol, d-arabitol, and l-arabitol, erwinia uredovora was able to utilize only d-arabitol as a carbon and energy source. although attempts to isolate ribitol- or l-arabitol-utilizing mutants were unsuccessful, mutants able to grow on xylitol were isolated at a frequency of 9 x 10(-8). xylitol-positive mutants constitutively synthesized both a novel nad-dependent xylitol-4-dehydrogenase, which oxidized xylitol to l-xylulose, and an l-xylulokinase. the xylitol dehyd ...19852981816
production of d- and l-xylulose by mutants of klebsiella pneumoniae and erwinia uredovora.d-xylulose and l-xylulose were produced biologically by the oxidation of a corresponding pentitol. a klebsiella pneumoniae mutant was constructed for the oxidation of d-arabitol to d-xylulose. this mutant constitutively synthesized the d-arabitol permease system and d-arabitol dehydrogenase but was unable to produce the d-xylulokinase of the d-arabitol pathway or the d-xylose isomerase and d-xylulokinase of the d-xylose pathway. an erwinia uredovora mutant which constitutively synthesized a nove ...19852983605
microbial metabolism of amino alcohols. metabolism of ethanolamine and 1-aminopropan-2-ol in species of erwinia and the roles of amino alcohol kinase and amino alcohol o-phosphate phospho-lyase in aldehyde formation.1. growth of erwinia carotovora n.c.p.p.b. 1280 on media containing 1-aminopropan-2-ol compounds or ethanolamine as the sole n source resulted in the excretion of propionaldehyde or acetaldehyde respectively. the inclusion of (nh(4))(2)so(4) in media prevented aldehyde formation. 2. growth, microrespirometric and enzymic evidence implicated amino alcohol o-phosphates as aldehyde precursors. an inducibly formed atp-amino alcohol phosphotransferase was partially purified and found to be markedly s ...19734357716
isolation of l-cycloserine from erwinia uredovora.an antibiotic which seems to be a cell wall synthesis-inhibitor was isolated from a bacteria strain identified as erwinia uredovora. the antibiotic was identified with l-cycloserine from its physico-chemical properties. this is the first example for isolation of l-cycloserine as a microbial product.19846501090
isolation and functional identification of a novel cdna for astaxanthin biosynthesis from haematococcus pluvialis, and astaxanthin synthesis in escherichia coli.we succeeded in isolating a novel cdna involved in astaxanthin biosynthesis from the green alga haematococcus pluvialis, by an expression cloning method using an escherichia coli transformant as a host that synthesizes beta-carotene due to the erwinia uredovora carotenoid biosynthesis genes. the cloned cdna was shown to encode a novel enzyme, beta-carotene ketolase (beta-carotene oxygenase), which converted beta-carotene to canthaxanthin via echinenone, through chromatographic and spectroscopic ...19957579184
structure and functional analysis of a marine bacterial carotenoid biosynthesis gene cluster and astaxanthin biosynthetic pathway proposed at the gene level.a carotenoid biosynthesis gene cluster for the production of astaxanthin was isolated from the marine bacterium agrobacterium aurantiacum. this cluster contained five carotenogenic genes with the same orientation, which were designated crtw, crtz, crty, crti, and crtb. the stop codons of individual crt genes except for crtb overlapped the start codons of the following crt genes. escherichia coli transformants carrying the erwinia uredovora carotenoid biosynthesis genes provide suitable substrate ...19957592436
large-scale production and purification of an erwinia ananas ice nucleation protein and evaluation of its ice nucleation activity.the ice nucleation-active protein of erwinia ananas in-10 (inaa protein) was over-expressed as inclusion bodies in escherichia coli in a yield of 15.3 mg of inaa protein from 60 mg of bacterial cells on a dry-matter basis. the inaa protein was purified from the inclusion bodies by solubilization with detergents to obtain a protein preparation free from sugar and lipid. this preparation had a distinct ice nucleation activity, indicating that the inaa protein per se is able to act as a nucleus.19937763657
cloning and sequencing of an ice nucleation active gene of erwinia uredovora.an ice nucleation activity gene, named inau, of the bacterium erwinia uredovora kuin-3 has been sequenced. this gene encodes a protein of 1034 amino acid residues, and its expression product, inau protein, has an 832-amino acid residue segment consisting of 52 repeats of closely related 16-amino acid motifs (r-domain), flanked by n- and c-terminal sequences (n- and c-domains, respectively). the primary structure of the inau protein is similar to those of the inaa, inaw, and inaz gene products of ...19947764866
expression of a tomato cdna coding for phytoene synthase in escherichia coli, phytoene formation in vivo and in vitro, and functional analysis of the various truncated gene products.full length and truncated cdna expression constructs of the phytoene synthase (psy) gene from tomato have been ligated into a puc8 cloning vector. one of the truncated constructs was introduced into escherichia coli carrying the erwinia uredovora ggpp synthase gene. this transformant produced 15,15'-cis-phytoene, which was identified on the basis of its uv and ir spectral data, from geranylgeranyl diphosphate. the function of this gene product was further confirmed by in vitro assay using cell-f ...19947896759
the arabidopsis ga1 locus encodes the cyclase ent-kaurene synthetase a of gibberellin biosynthesis.the first committed step in the gibberellin (ga) biosynthetic pathway is the conversion of geranylgeranyl pyrophosphate (ggpp) through copalyl pyrophosphate (cpp) to ent-kaurene catalyzed by ent-kaurene synthetases a and b. the ga1 mutants of arabidopsis are gibberellin-responsive male-sterile dwarfs. biochemical studies indicate that biosynthesis of gas in the ga1 mutants is blocked prior to the synthesis of ent-kaurene. the ga1 locus was cloned previously using the technique of genomic subtrac ...19947994182
archaebacterial ether-linked lipid biosynthetic gene. expression cloning, sequencing, and characterization of geranylgeranyl-diphosphate synthase.archaebacterial sulfolobus acidocaldarius geranylgeranyl-diphosphate (ggpp) synthase (ec 2.5.1.29) catalyzes consecutive condensations of isopentenyl diphosphate with allylic diphosphates to produce ggpp which is the important precursor of archaebacterial ether-linked lipids. we developed an expression screening method for cloning the ggpp synthase gene, which utilizes the carotenoid biosynthesis genes of erwinia uredovora to visualize a clone expressing ggpp synthase, and then screened a genomi ...19948182085
purification and enzymatic characterization of the geranylgeranyl pyrophosphate synthase from erwinia uredovora after expression in escherichia coli.geranylgeranyl pyrophosphate (ggpp) synthase from erwinia uredovora was overexpressed in escherichia coli and purified to homogeneity from solubilized inclusion bodies. in this protein the first 13 n-terminal amino acids were replaced by 16 other amino acids resulting from the cloning vector puc18. nevertheless, the enzyme showed activity after purification which could be stimulated sixfold by appropriate activation conditions. the homogeneous enzyme was used to study substrate and product speci ...19938215396
functional expression of the erwinia uredovora carotenoid biosynthesis gene crtl in transgenic plants showing an increase of beta-carotene biosynthesis activity and resistance to the bleaching herbicide norflurazon.among the enzymes involved in carotenoid biosynthesis, phytoene desaturase is considered to be a rate-limiting enzyme in this pathway and is also the target of many bleaching herbicides. this enzyme shows diversity concerning its function and amino acid homology among various organisms. the phytoene desaturase gene crtl of erwinia uredovora was expressed, the 5'-region of which was fused to the sequence for the transit peptide of a pea rubisco small subunit, in tobacco plants under the control o ...19938275101
functional identification of al-3 from neurospora crassa as the gene for geranylgeranyl pyrophosphate synthase by complementation with crt genes, in vitro characterization of the gene product and mutant analysis.in this work the neurospora crassa al-3 gene function was determined. geranylgeranyl pyrophosphate (ggpp) synthase activity was measured in al-2 fgsc 313 and al-3 rp100 fgsc 2082 mutant strains by in vitro synthesis methods. this experiment showed that al-3 rp100 mutant expresses a reduced ggpp synthase activity. the mutated al-3 gene was cloned and sequenced; a single missense mutation was found changing serine into asparagine. genetic complementation was performed by escherichia coli transform ...19938350190
expression, purification and properties of lycopene cyclase from erwinia uredovora.lycopene cyclase, an enzyme responsible for the formation of cyclic carotenoids from acyclic precursors has been purified to homogeneity in an active state. the erwinia uredovora lycopene cyclase gene (crty) was over-expressed in escherichia coli. from this recombinant strain the enzyme was purified by immuno-affinity chromatography and its cyclization activity characterized as a two-step reaction in which both sides of the lycopene molecule are cyclized to beta-ionone rings with the monocyclic ...19968645170
significance of the c-terminal domain of erwinia uredovora ice nucleation-active protein (ina u).ice nucleation-active (ina) proteins of bacterial origin comprise three distinct domains, i.e., n-terminal (n-), central repeat (r-), and c-terminal (c-) domains, among which the r-domain is essential, and its length may be correlated with the ice nucleation activity. in addition, the short c-terminal domain of about 50 amino acid residues is indispensable for the activity. using the ina u protein of erwinia uredovora, we carried out precise mutational analyses of its c-terminus. the ice nucleat ...19958720147
expression in escherichia coli and properties of the carotene ketolase from haematococcus pluvialis.high level expression of the functional beta-carotene ketolase gene bkt from haematococcus pluvialis occurred in escherichia coli transformants producing beta-carotene or zeaxanthin as a result of the presence of additional carotenoid genes from erwinia uredovora. requirement of molecular oxygen for the insertion of the keto group was demonstrated. the final product of this two-step ketolase reaction from beta-carotene is canthaxanthin (4,4'-diketo-beta-carotene) with the 4-monoketo derivative e ...19968764486
biochemical characteristics of enterobacter agglomerans and related strains found in buckwheat seeds.thirty strains of bacteria were randomly isolated and identified from buckwheat seeds. the phenotypic characteristics of these strains agree well with those of the enterobacter agglomerans-erwinia herbicola complex. on the basis of the difference in indole production and gas production from d-glucose, the isolates were divided into 3 phenotypic groups, viz. i, ii and iii. twenty two strains were in phenotypic group 1, which is negative for indole production and gas production from d-glucose, and ...19968854178
the carotenoid 7,8-dihydro-psi end group can be cyclized by the lycopene cyclases from the bacterium erwinia uredovora and the higher plant capsicum annuum.the genes for geranylgeranyl diphosphate synthase (crte) and phytoene synthase (crtb) from the epiphytic bacterium erwinia uredovora and the phytoene desaturase gene from the photosynthetic bacterium rhodobacter capsulatus (rc-crti) were introduced into escherichia coli, which resulted in the accumulation of the acyclic carotenoid, neurosporene. further introduction of the lycopene cyclase gene from e. uredovora (crty) or the higher plant capsicum annuum (icy) resulted in the production of a bic ...19968898919
in vitro characterization of astaxanthin biosynthetic enzymes.escherichia coli strains expressing the marine bacteria (agrobacterium aurantiacum and alcaligenes sp. strain pc-1) astaxanthin biosynthetic genes (crtz and w), haematococcus pluvialis bkt, and erwinia uredovora crtz genes were used for in vitro characterization of the respective enzymes. specific enzyme assays indicated that all of the enzymes are bifunctional, in that the crtz enzymes formed zeaxanthin from beta-carotene via beta-cryptoxanthin, as well as astaxanthin from canthaxanthin via pho ...19979045623
cloning and functional expression of a novel geranylgeranyl pyrophosphate synthase gene from arabidopsis thaliana in escherichia coli.a gene encoding a novel geranylgeranyl pyrophosphate (ggpp) synthase from arabidopsis thaliana has been identified and termed ggps5. the gene has been sequenced and expressed in escherichia coli. the deduced amino acid sequence showed 64.5% and 57.5% identify with a putative ggpp synthase from arabidopsis and capsicum annuum, respectively. ggpp enzymatic activity was detected in e. coli cells expressing the ggps5 gene in two different ways. one was the direct measurement of ggpp synthase activit ...19979150607
cloning, sequencing and expressing the carotenoid biosynthesis genes, lycopene cyclase and phytoene desaturase, from the aerobic photosynthetic bacterium erythrobacter longus sp. strain och101 in escherichia coli.two genes which encode the enzymes lycopene cyclase and phytoene desaturase in the aerobic photosynthetic bacterium erythrobacter longus sp. strain och101 have been cloned and sequenced. the gene for lycopene cyclase, designated crty, was expressed in a strain of escherichia coli which contained the crte, b, i and z genes encoding geranylgeranyl pyrophosphate synthase, phytoene synthase, phytoene desaturase, and beta-carotene hydroxylase, respectively. as a result, zeaxanthin production was obse ...19979168123
phylogenetic analysis of erwinia species based on 16s rrna gene sequences.the phylogenetic relationships of the type strains of 16 erwinia species were investigated by performing a comparative analysis of the sequences of the 16s rrna genes of these organisms. the sequence data were analyzed by the neighbor-joining method, and each branch was supported by moderate bootstrap values. the phylogenetic tree and sequence analyses confirmed that the genus erwinia is composed of species that exhibit considerable heterogeneity and form four clades that are intermixed with mem ...19979336906
geranylgeranyl pyrophosphate synthase encoded by the newly isolated gene ggps6 from arabidopsis thaliana is localized in mitochondria.we have cloned a new geranylgeranyl pyrophosphate (ggpp) synthase gene, designated ggps6, from arabidopsis thaliana genomic dna. nucleotide sequence analysis revealed that the ggps6 gene contains an open reading frame coding for a protein of 343 amino acid residues with a calculated molecular mass of 37,507 da. also, the gene is not interrupted by an intron. the predicted amino acid sequence of the ggps6 gene shows significant homology (34.0-57.7%) with other ggpp synthases from arabidopsis. the ...19979349257
first report of a human isolate of erwinia persicinus.erwinia persicinus was first described in 1990 after being isolated from a variety of fruits and vegetables, including bananas, cucumbers, and tomatoes. in 1994, it was shown to be the causative agent of necrosis of bean pods. we now report the first human isolate of e. persicinus. the strain was isolated from the urine of an 88-year-old woman who presented with a urinary tract infection. by the hydroxyapatite method, dna from this strain was shown to be 94.5% related at 60 degrees c and 86% rel ...19989431957
synthesis of atypical cyclic and acyclic hydroxy carotenoids in escherichia coli transformants.a total of eight different hydroxy carotenoids were produced in transformants of the non-carotenogenic bacterium escherichia coli. they include the acyclic 1-hydroxyneurosporene, 1-hydroxylycopene, 1,1'-dihydroxylycopene and demethylspheroidene as well as the cyclic 3-hydroxy-beta-zeacarotene, 7,8-dihydrozeaxanthin, 3 or 3'-7,8-dihydro-beta-carotene and 1'-hydroxy-gamma-carotene. most of these uncommon carotenoids are found only in trace amounts in natural sources. for the synthesis of all the c ...19979470222
production of the carotenoids lycopene, beta-carotene, and astaxanthin in the food yeast candida utilis.the food-grade yeast candida utilis has been engineered to confer a novel biosynthetic pathway for the production of carotenoids such as lycopene, beta-carotene, and astaxanthin. the exogenous carotenoid biosynthesis genes were derived from the epiphytic bacterium erwinia uredovora and the marine bacterium agrobacterium aurantiacum. the carotenoid biosynthesis genes were individually modified based on the codon usage of the c. utilis glyceraldehyde 3-phosphate dehydrogenase gene and expressed in ...19989546156
evaluation of structurally different carotenoids in escherichia coli transformants as protectants against uv-b radiation.escherichia coli cells transformed with several carotenogenic genes to mediate the formation of zeta-carotene, neurosporene, lycopene, beta-carotene, and zeaxanthin were exposed to uv-b radiation. short-term kinetics revealed that endogenous levels of neurosporene and beta-carotene protected e. coli against irradiation with uv-b. zeaxanthin protected against only the photosensitized uv-b treatment. all other carotenoids were ineffective.19989572984
expression of an active phytoene synthase from erwinia uredovora and biochemical properties of the enzyme.the crtb gene encoding phytoene synthase from the carotenogenic enterobacterium erwinia uredovora was overexpressed to about 20% of the total cellular protein in escherichia coli. formation of the active phytoene synthase had the effect of suppressing the growth of the expressing strain. presumably inhibition of growth arose from the depletion of the substrate geranylgeranyl pyrophosphate (ggpp) which, in e. coli, is necessary for the synthesis of essential prenylpyrophosphate derivatives. in or ...19989593819
pcr-based detection of the causal agent of watermark disease in willows (salix spp.)the watermark disease, caused by brenneria salicis (formerly erwinia salicis), is of significant concern wherever tree-forming willows are grown or occur naturally. the movement of infected, asymptomatic cuttings is a major cause of pathogen dispersal. a reliable and sensitive diagnostic procedure is necessary for the safe movement of willow planting material. we derived primers from the nucleotide sequence of the 16s rrna gene of b. salicis for the development of a pcr to detect this pathogen. ...19989758827
engineered isoprenoid pathway enhances astaxanthin production in escherichia coli.the isoprenoid pathway is a versatile biosynthetic network leading to over 23,000 compounds. similar to other biosynthetic pathways, the production of isoprenoids in microorganisms is controlled by the supply of precursors, among other factors. to engineer a host that has the capability to supply geranylgeranyl diphosphate (ggpp), a common precursor of isoprenoids, we cloned and overexpressed isopentenyl diphosphate (ipp) isomerase (encoded by idi) from escherichia coli and ggpp synthase (encode ...199910099534
identification of the ggps1 genes encoding geranylgeranyl diphosphate synthases from mouse and human.e,e,e-geranylgeranyl diphosphate (ggpp) is an important precursor of carotenoids and geranylgeranylated proteins such as small g proteins. in this study, we have identified mouse and human ggpp synthase genes. sequence analysis showed that mouse and human ggpp synthases share a high level of amino acid identity (94%) with each other, and share a high level of similarity (45-50%) with ggpp synthases of lower eukaryotes, but only weak similarity (22-31%) to plant and prokaryotic ggpp synthases. bo ...199910101267
production of lycopene by the food yeast, candida utilis that does not naturally synthesize carotenoid.the erwinia uredovora crte, crtb, and crti genes, which are responsible for the synthesis of carotenoid lycopene from farnesyl pyrophosphate, were expressed in candida utilis under the control of the promoters and terminators derived from the c. utilis gap, pgk, and pma genes, respectively. the yeast transformant carrying the carotenoid biosynthesis genes produced 758 microg/g dry weight of lycopene along with 407 microg/g dry weight of phytoene in the stationary phase. it was observed in the c. ...199810191407
protection of photosynthesis against ultraviolet-b radiation by carotenoids in transformants of the cyanobacterium synechococcus pcc7942the cyanobacterium synechococcus pcc7942 was transformed with various carotenogenic genes, and the resulting transformants either accumulated higher amounts of beta-carotene and zeaxanthin or showed a shift in the carotenoid pattern toward the formation of zeaxanthin. these transformants were exposed to ultraviolet-b (uv-b) radiation, and the degradation of phycobilins, the inactivation of photosynthetic oxygen evolution, and the activity of photosystem ii were determined. in the genetically mod ...199910364412
cloning and characterization of the astaxanthin biosynthetic gene encoding phytoene desaturase of xanthophyllomyces dendrorhous.the first carotenoid biosynthetic gene from the basidiomycetous yeast xanthophyllomyces dendrorhous was isolated by heterologous complementation in escherichia coli. the isolated gene, denominated as crti, was found to encode for phytoene desaturase. the coding region is interrupted by 11 introns. the deduced amino acid sequence showed significant homology with its bacterial and eukaryotic counterparts, especially those of fungal origin. a plasmid containing the geranylgeranyl diphosphate syntha ...199910397832
gut colonization by an ice nucleation active bacterium, erwinia (pantoea) ananas reduces the cold hardiness of mulberry pyralid larvae.to evaluate the suitability of using ice nucleation active (ina) bacteria for the biological control of insect pests, the supercooling point (scp) of larvae of mulberry pyralid, glyphodes duplicalis, and silkworm, bombyx mori, ingesting ina strains of erwinia (pantoea) ananas and pseudomonas syringae was determined. mean scp of the guts of silkworm larvae ingesting ina strains of e. ananas ranged from -2.5 to -2.8 degrees c, being 5 degrees c higher than that in control treatments. similarly, me ...199910413571
biological control of an insect pest by gut-colonizing enterobacter cloacae transformed with ice nucleation gene.the ice nucleation (in) gene inaa of epiphytic erwinia (pantoea) ananas in10 was transformed into enterobacter cloacae wbmh-3-cmr originated from the faeces of silkworms. the transformant designated as ent. cloacae wbmh-3-cmr(pice6s13) exhibited in activity, unlike the parent strain. the transgenic strain was ingested by mulberry pyralid larvae, fed on detached mulberry leaves, and the supercooling capacity and cold hardiness of these larvae were examined. the mean supercooling point (scp) of th ...200010735247
metabolic engineering of carotenoid accumulation in escherichia coli by modulation of the isoprenoid precursor pool with expression of deoxyxylulose phosphate synthase.the recently discovered non-mevalonate pathway to isoprenoids, which uses glycolytic intermediates, has been modulated by overexpression of escherichia coli d-1-deoxyxylulose 5-phosphate synthase (dxs) to increase deoxyxylulose 5-phosphate and, consequently, increase the isoprenoid precursor pool in e. coli. carotenoids are a large class of biologically important compounds synthesized from isoprenoid precursors and of interest for metabolic engineering. however, carotenoids are not ordinarily pr ...200010803894
isolation and characterization of canthaxanthin biosynthesis genes from the photosynthetic bacterium bradyrhizobium sp. strain ors278.a carotenoid biosynthesis gene cluster involved in canthaxanthin production was isolated from the photosynthetic bradyrhizobium sp. strain ors278. this cluster includes five genes identified as crte, crty, crti, crtb, and crtw that are organized in at least two operons. the functional assignment of each open reading frame was confirmed by complementation studies.200010851005
false fertilization in sea urchin eggs induced by diabolin, a 120k kelp protein.a 120k lectin-like protein was isolated from the kelp laminaria diabolica (oni-kombu), with a unique activity to induce false fertilization specifically in the eggs of the sea urchin hemicentrotus pulcherrimus. the protein designated as "diabolin" rendered the unfertilized egg forms and elevated the fertilization envelope without insemination at 18 nm half-maximally. those eggs with elevated fertilization envelopes, however, could not enter into normal cleavage or further development, and hence ...200010860816
bacteria in the leaf ecosystem with emphasis on pseudomonas syringae-a pathogen, ice nucleus, and epiphyte.the extremely large number of leaves produced by terrestrial and aquatic plants provide habitats for colonization by a diversity of microorganisms. this review focuses on the bacterial component of leaf microbial communities, with emphasis on pseudomonas syringae-a species that participates in leaf ecosystems as a pathogen, ice nucleus, and epiphyte. among the diversity of bacteria that colonize leaves, none has received wider attention than p. syringae, as it gained notoriety for being the firs ...200010974129
recommended conservation of the names streptococcus sanguis, streptococcus rattus, streptococcus cricetus, and seven other names included in the approved lists of bacterial names. request for an opinion.with reference to the first principle of the international code of nomenclature of bacteria, which emphasizes stability of names, it is proposed that the original names streptococcus sanguis, streptococcus rattus, streptococcus cricetus, erwinia ananas, eubacterium tarantellus, lactobacillus sake, nitrosococcus oceanus, pseudomonas betle, rickettsia canada and streptomyces rangoon, all included in the approved lists of bacterial names, be conserved. request for an opinion.200111321121
biosynthesis of beta-carotene (provitamin a) in rice endosperm achieved by genetic engineering.to obtain a functioning provitamin a (beta-carotene) biosynthetic pathway in rice endosperm, we introduced in a single, combined transformation effort the cdnas coding for (1) phytoene synthase (psy) and (2) lycopene beta-cyclase (beta-lcy; both from narcissus pseudonarcissus and both under control of the endosperm-specific glutelin promoter), with (3) a bacterial phytoene desaturase (crti, from erwinia uredovora under constitutive 35s promoter control). this combination covers the requirements ...200111387982
rapid identification and differentiation of the soft rot erwinias by 16s-23s intergenic transcribed spacer-pcr and restriction fragment length polymorphism analyses.current identification methods for the soft rot erwinias are both imprecise and time-consuming. we have used the 16s-23s rrna intergenic transcribed spacer (its) to aid in their identification. analysis by its-pcr and its-restriction fragment length polymorphism was found to be a simple, precise, and rapid method compared to current molecular and phenotypic techniques. the its was amplified from erwinia and other genera using universal pcr primers. after pcr, the banding patterns generated allow ...200111526007
effect of solar uv-b radiation on a phyllosphere bacterial community.the effect of solar uv-b radiation on the population dynamics and composition of the culturable bacterial community from peanut (arachis hypogeae l.) was examined in field studies using plants grown under uv-b-transmitting (uv-b+) or uv-b-excluding (uv-b-) plastic filters. our data demonstrate that solar uv-b selection alters phyllosphere bacterial community composition and that uv tolerance is a prevalent phenotype late in the season. the total bacterial population size was not affected by eith ...200111722897
novel medium-chain prenyl diphosphate synthase from the thermoacidophilic archaeon sulfolobus solfataricus.two open reading frames which encode the homologues of (all-e) prenyl diphosphate synthase are found in the whole-genome sequence of sulfolobus solfataricus, a thermoacidophilic archaeon. it has been suggested that one is a geranylgeranyl diphosphate synthase gene, but the specificity and biological significance of the enzyme encoded by the other have remained unclear. thus, we isolated the latter by the pcr method, expressed the enzyme in escherichia coli cells, purified it, and characterized i ...200211790729
evaluation of transgenic tomato plants expressing an additional phytoene synthase in a fruit-specific manner.phytoene synthase from the bacterium erwinia uredovora (crtb) has been overexpressed in tomato (lycopersicon esculentum mill. cv. ailsa craig). fruit-specific expression was achieved by using the tomato polygalacturonase promoter, and the crtb protein was targeted to the chromoplast by the tomato phytoene synthase-1 transit sequence. total fruit carotenoids of primary transformants (t(0)) were 2-4-fold higher than the controls, whereas phytoene, lycopene, beta-carotene, and lutein levels were in ...200211805345
genotyping of bacteria belonging to the former erwinia genus by pcr-rflp analysis of a reca gene fragment.genotypic characterization, based on the analysis of restriction fragment length polymorphism of the reca gene fragment pcr product (reca pcr-rflp), was performed on members of the former erwinia genus. pcr primers deduced from published reca gene sequences of erwinia carotovora allowed the amplification of an approximately 730 bp dna fragment from each of the 19 erwinia species tested. amplified reca fragments were compared using rflp analysis with four endonucleases (alui, hinfi, tasi and tru1 ...200211832521
golden rice: introducing the beta-carotene biosynthesis pathway into rice endosperm by genetic engineering to defeat vitamin a deficiency.to obtain a functioning provitamin a (beta-carotene) biosynthetic pathway in rice endosperm, we introduced in a single, combined transformation effort the cdna coding for phytoene synthase (psy) and lycopene beta-cyclase (beta-lcy) both from narcissus pseudonarcissus and both under the control of the endosperm-specific glutelin promoter together with a bacterial phytoene desaturase (crti, from erwinia uredovora under constitutive 35s promoter control). this combination covers the requirements fo ...200211880581
application of amplified fragment length polymorphism fingerprinting for taxonomy and identification of the soft rot bacteria erwinia carotovora and erwinia chrysanthemi.the soft rot bacteria erwinia carotovora and erwinia chrysanthemi are important pathogens of potato and other crops. however, the taxonomy of these pathogens, particularly at subspecies level, is unclear. an investigation using amplified fragment length polymorphism (aflp) fingerprinting was undertaken to determine the taxonomic relationships within this group based on their genetic relatedness. following cluster analysis on the similarity matrices derived from the aflp gels, four clusters (clus ...200211916661
identification of a lycopene beta-cyclase required for bacteriorhodopsin biogenesis in the archaeon halobacterium salinarum.biogenesis of the light-driven proton pump bacteriorhodopsin in the archaeon halobacterium salinarum requires coordinate synthesis of the bacterioopsin apoprotein and carotenoid precursors of retinal, which serves as a covalently bound cofactor. as a step towards elucidating the mechanism and regulation of carotenoid metabolism during bacteriorhodopsin biogenesis, we have identified an h. salinarum gene required for conversion of lycopene to beta-carotene, a retinal precursor. the gene, designat ...200212003928
response of the ice-nucleating bacterium pantoea ananas kuin-3 during cold acclimation.the ice-nucleating bacterium pantoea ananas kuin-3 accumulated glucose in cells following a shift in temperature (10 degrees c) from the optimum growth temperature (30 degrees c). this accumulation might be caused by the activation of glucose-6-phosphatase. although this strain after culturing at 30 degrees c was harmed by freezing, the cryotolerance of this strain was reached about 80% after cold acclimation at 10 degrees c.200212036064
expression of a bacterial carotene hydroxylase gene (crtz) enhances uv tolerance in tobacco.carotenoids are essential components of the photosynthetic apparatus involved in plant photoprotection. to investigate the protective role of zeaxanthin under high light and uv stress we have increased the capacity for its biosynthesis in tobacco plants (nicotiana tabacum l. cv. samsun) by transformation with a heterologous carotenoid gene encoding beta-carotene hydroxylase (crtz) from erwinia uredovora under constitutive promoter control. this enzyme is responsible for the conversion of beta-ca ...200212139004
expression of erwinia uredovora phytoene desaturase in synechococcus pcc7942 leading to resistance against a bleaching herbicide.the gene coding for phytoene desaturase of the bacterium erwinia uredovora (crti) was inserted into the chromosome of the cyanobacterium synechococcus pcc7942 strain r2-pim8. for expression of crti in the heterologous host, two constructs with different promoters were introduced into synechococcus. in the first, crti was fused to the 5[prime] region of the psba gene of the xanthophycean microalga bumilleriopsis filiformis. the second construct carried crti inserted downstream of the neomycin pho ...199412232067
evolution of the c30 carotenoid synthase crtm for function in a c40 pathway.the c30 carotene synthase crtm from staphylococcus aureus and the c40 carotene synthase crtb from erwinia uredovora were swapped into their respective foreign c40 and c30 biosynthetic pathways (heterologously expressed in escherichia coli) and evaluated for function. each displayed negligible ability to synthesize the natural carotenoid product of the other. after one round of mutagenesis and screening, we isolated 116 variants of crtm able to synthesize c40 carotenoids. in contrast, we failed t ...200212426357
response of escherichia coli containing mycobacterial carotene genes to uv radiation.the plasmid pc5, which encodes biogenesis of lycopene in mycobacterium aurum a(+), was partially digested by restriction endonucleases and generated fragments were cloned. after transformation of escherichia coli (colorless bacteria) with the plasmids so constructed, seven orange clones were detected and found to carry the same recombinant plasmid (pc51). e. coli cells containing this plasmid synthesize neurosporene and lycopene, and were more resistant to ultraviolet irradiation than non pigmen ...200112488613
crystal structure of the murg:udp-glcnac complex reveals common structural principles of a superfamily of glycosyltransferases.murg is an essential glycosyltransferase that forms the glycosidic linkage between n-acetyl muramyl pentapeptide and n-acetyl glucosamine in the biosynthesis of the bacterial cell wall. this enzyme is a member of a major superfamily of ndp-glycosyltransferases for which no x-ray structures containing intact substrates have been reported. here we present the 2.5-a crystal structure of escherichia coli murg in complex with its donor substrate, udp-glcnac. combined with genomic analysis of other su ...200312538870
surrogate biochemistry: use of escherichia coli to identify plant cdnas that impact metabolic engineering of carotenoid accumulation.carotenoids synthesized in plants but not animals are essential for human nutrition. therefore, ongoing efforts to metabolically engineer plants for improved carotenoid content benefit from the identification of genes that affect carotenoid accumulation, possibly highlighting potential challenges when pyramiding traits represented by multiple biosynthetic pathways. we employed a heterologous bacterial system to screen for maize cdnas encoding products that alter carotenoid accumulation either po ...200312664151
new insight into phaeodactylum tricornutum fatty acid metabolism. cloning and functional characterization of plastidial and microsomal delta12-fatty acid desaturases.in contrast to 16:3 plants like rapeseed (brassica napus), which contain alpha-linolenic acid (18:3(delta9,12,15)) and hexadecatrienoic acid (16:3(delta7,10,13)) as major polyunsaturated fatty acids in leaves, the silica-less diatom phaeodactylum tricornutum contains eicosapentaenoic acid (epa; 20:5(delta5,8,11,14,17)) and a different isomer of hexadecatrienoic acid (16:3(delta6,9,12)). in this report, we describe the characterization of two cdnas having sequence homology to delta12-fatty acid d ...200312692324
a c35 carotenoid biosynthetic pathway.upon coexpression with erwinia geranylgeranyldiphosphate (ggdp) synthase in escherichia coli, c(30) carotenoid synthase crtm from staphylococcus aureus produces novel carotenoids with the asymmetrical c(35) backbone. the products of condensation of farnesyldiphosphate and gdp, c(35) structures comprise 40 to 60% of total carotenoid accumulated. carotene desaturases and carotene cyclases from c(40) or c(30) pathways accepted and converted the c(35) substrate, thus creating a c(35) carotenoid bios ...200312788765
method to protect a targeted amino acid residue during random mutagenesis.to generate a random mutant library that is free from mutation at a particular amino acid residue, we replace the codon of interest with a detachable, short dna sequence containing a bsaxi recognition site. after pcr mutagenesis, this sequence is removed and intramolecular ligation of the sequences flanking the insert regenerates the gene. the three-base cohesive ends for ligation correspond to the codon for the targeted residue and any sequences with mutations at this site will fail to ligate. ...200312907743
taxonomic relationships of xanthomonas uredovorus. 196113905696
properties of a novel extracellular cell-free ice nuclei from ice-nucleating pseudomonas antarctica in-74.some ice-nucleating bacterial strains, including pantoea ananatis (erwinia uredovora), pseudomonas fluorescens, and pseudomonas syringae isolates, were examined for the ability to shed ice nuclei into the growth medium. a novel ice-nucleating bacterium, pseudomonas antarctica in-74, was isolated from ross island, antarctica. cell-free ice nuclei from p. antarctica in-74 were different from the conventional cell-free ice nuclei and showed a unique characterization. cell-free ice nuclei were purif ...200314519981
cyp175a1 from thermus thermophilus hb27, the first beta-carotene hydroxylase of the p450 superfamily.the biological function of thermostable p450 monooxygenase cyp175a1 from thermus thermophilus hb27 was studied by functional complementation in escherichia coli. the gene product of cyp175a1 added hydroxyl groups to both beta rings of beta-carotene to form zeaxanthin (beta,beta-carotene-3,3'-diol) in e. coli, which produces beta-carotene due to the erwinia uredovora carotenoid biosynthesis genes. in addition, spectroscopic methods revealed that e. coli carrying cyp175a1 and the cdna of the haema ...200414727092
evolution of a pathway to novel long-chain carotenoids.using methods of laboratory evolution to force the c(30) carotenoid synthase crtm to function as a c(40) synthase, followed by further mutagenesis at functionally important amino acid residues, we have discovered that synthase specificity is controlled at the second (rearrangement) step of the two-step reaction. we used this information to engineer crtm variants that can synthesize previously unknown c(45) and c(50) carotenoid backbones (mono- and diisopentenylphytoenes) from the appropriate iso ...200414973014
genomic and genetic analysis of bordetella bacteriophages encoding reverse transcriptase-mediated tropism-switching cassettes.liu et al. recently described a group of related temperate bacteriophages that infect bordetella subspecies and undergo a unique template-dependent, reverse transcriptase-mediated tropism switching phenomenon (liu et al., science 295: 2091-2094, 2002). tropism switching results from the introduction of single nucleotide substitutions at defined locations in the vr1 (variable region 1) segment of the mtd (major tropism determinant) gene, which determines specificity for receptors on host bacteria ...200414973019
bacteremic infection with pantoea ananatis.a 73-year-old man was hospitalized for dyspnea and bilateral ankle edema. during his hospital stay he presented anal hemorrhage and developed a high fever after colonoscopy. a set of aerobic and anaerobic blood culture bottles yielded a pure culture of gram-negative rods, susceptible to all antibiotics tested. the api20e code was 1005133, resulting in a very good identification as pantoea sp. subsequent sequencing of the 16s rrna gene revealed a final identification as pantoea ananatis. the pati ...200415365053
metabolic engineering of high carotenoid potato tubers containing enhanced levels of beta-carotene and lutein.in order to enhance the carotenoid content of potato tubers, transgenic potato plants have been produced expressing an erwinia uredovora crtb gene encoding phytoene synthase, specifically in the tuber of solanum tuberosum l. cultivar desiree which normally produces tubers containing c. 5.6 microg carotenoid g(-1) dw and also in solanum phureja l. cv. mayan gold which has a tuber carotenoid content of typically 20 microg carotenoid g(-1) dw. in developing tubers of transgenic crtb desiree lines, ...200515533882
molecular cloning and functional expression of geranylgeranyl pyrophosphate synthase from coleus forskohlii briq.isopentenyl diphosphate (ipp), a common biosynthetic precursor to the labdane diterpene forskolin, has been biosynthesised via a non-mevalonate pathway. geranylgeranyl diphosphate (ggpp) synthase is an important branch point enzyme in terpenoid biosynthesis. therefore, ggpp synthase is thought to be a key enzyme in biosynthesis of forskolin. herein we report the first confirmation of the ggpp synthase gene in coleus forskohlii briq.200415550168
protein domains and architectural innovation in plant-associated proteobacteria.evolution of new complex biological behaviour tends to arise by novel combinations of existing building blocks. the functional and evolutionary building blocks of the proteome are protein domains, the function of a protein being dependent on its constituent domains. we clustered completely-sequenced proteomes of prokaryotes on the basis of their protein domain content, as defined by pfam (release 16.0). this revealed that, although there was a correlation between phylogeny and domain content, ot ...200515715905
diversifying carotenoid biosynthetic pathways by directed evolution.microorganisms and plants synthesize a diverse array of natural products, many of which have proven indispensable to human health and well-being. although many thousands of these have been characterized, the space of possible natural products--those that could be made biosynthetically--remains largely unexplored. for decades, this space has largely been the domain of chemists, who have synthesized scores of natural product analogs and have found many with improved or novel functions. new natural ...200515755953
improving the nutritional value of golden rice through increased pro-vitamin a content."golden rice" is a variety of rice engineered to produce beta-carotene (pro-vitamin a) to help combat vitamin a deficiency, and it has been predicted that its contribution to alleviating vitamin a deficiency would be substantially improved through even higher beta-carotene content. we hypothesized that the daffodil gene encoding phytoene synthase (psy), one of the two genes used to develop golden rice, was the limiting step in beta-carotene accumulation. through systematic testing of other plant ...200515793573
genome-based examination of chlorophyll and carotenoid biosynthesis in chlamydomonas reinhardtii.the unicellular green alga chlamydomonas reinhardtii is a particularly important model organism for the study of photosynthesis since this alga can grow heterotrophically, and mutants in photosynthesis are therefore conditional rather than lethal. the recently developed tools for genomic analyses of this organism have allowed us to identify most of the genes required for chlorophyll and carotenoid biosynthesis and to examine their phylogenetic relationships with homologous genes from vascular pl ...200515849308
evolutionary relationships of three new species of enterobacteriaceae living as symbionts of aphids and other insects.ecological studies on three bacterial lineages symbiotic in aphids have shown that they impose a variety of effects on their hosts, including resistance to parasitoids and tolerance to heat stress. phylogenetic analyses of partial sequences of gyrb and reca are consistent with previous analyses limited to 16s rrna gene sequences and yield improved confidence of the evolutionary relationships of these symbionts. all three symbionts are in the enterobacteriaceae. one of the symbionts, here given t ...200515933033
pa 20, a semi-selective medium for isolation and enumeration of pantoea ananatis.a semi-selective medium, pa 20, was developed for the isolation and enumeration of pantoea ananatis from plant material, specifically from onion seed. the medium has a ph of 8.0 and contains nh4h2po4, k2hpo4, magnesium sulphate, nacl, d (+) arabitol, crystal violet, bromothymol blue and thallium nitrate. all p. ananatis strains from a variety of hosts produced characteristic yellow colonies in 6-7 days at 25 degrees c. plating efficiencies on pa 20 in comparison to nutrient agar ranged from 92 t ...200615979177
elucidation of a carotenoid biosynthesis gene cluster encoding a novel enzyme, 2,2'-beta-hydroxylase, from brevundimonas sp. strain sd212 and combinatorial biosynthesis of new or rare xanthophylls.a carotenoid biosynthesis gene cluster mediating the production of 2-hydroxyastaxanthin was isolated from the marine bacterium brevundimonas sp. strain sd212 by using a common crti sequence as the probe dna. a sequence analysis revealed this cluster to contain 12 open reading frames (orfs), including the 7 known genes, crtw, crty, crti, crtb, crte, idi, and crtz. the individual orfs were functionally analyzed by complementation studies using escherichia coli that accumulated various carotenoid p ...200516085816
purification and properties of an ice-nucleating protein from an ice-nucleating bacterium, pantoea ananatis kuin-3.an ice-nucleating protein (inp) from the extracellular ice-nucleating matter (eim) of pantoea ananatis (erwinia uredovora) kuin-3 was purified and characterized. the eim produced by the strain kuin-3 was purified by ultrafiltration, sucrose density-gradient ultracentrifugation and gel filtration. the inp was purified using of column chromatography on hydroxyapatite and superdex 200 in the nondenaturing detergent of 0.1% (w/v) triton x-100. the purified inp was composed of one subunit of 117 kda ...200316233385
effect of freeze-thaw repetitions upon the supercooling release ability of ice-nucleating bacteria.we have studied the durability of ice-nucleating bacteria with a potent supercooling release capacity through repeated freeze-thaw cycles. through experiment, we confirmed that uv sterilized erwinia ananas maintains a superior supercooling release capacity at around -1 degrees c through 2000 freeze-thaw cycles. we also found that gamma-ray sterilization, which is more suitable than uv for large-scale sterilization treatment, has a similar effect at appropriately selected doses.200416233592
characterization of microbial contamination in united states air force aviation fuel tanks.bacteria and fungi, isolated from united states air force (usaf) aviation fuel samples, were identified by gas chromatograph fatty acid methyl ester (gc-fame) profiling and 16s or 18s rrna gene sequencing. thirty-six samples from 11 geographically separated usaf bases were collected. at each base, an above-ground storage tank, a refueling truck, and an aircraft wing tank were sampled at the lowest sample point, or sump, to investigate microbial diversity and dispersion within the fuel distributi ...200616328508
transgenic ice nucleation-active enterobacter cloacae reduces cold hardiness of corn borer and cotton bollworm larvae.the ice nucleation (in) gene icea of erwinia ananas 110 was integrated into the chromosomes of two enterobacter cloacae strains (enc1.2022 and enc1.181). these two newly derived transgenic strains, designated enc2022-i and enc181-i, respectively, possessed ice nucleation activity at -2.5 degrees c, significantly higher than their parent strains (active at approx -10 degrees c or lower). after ingesting these transgenic bacteria, the mean supercooling points (scps) of corn borer and cotton bollwo ...200416329857
diversity of carotenoid synthesis gene clusters from environmental enterobacteriaceae strains.eight enterobacteriaceae strains that produce zeaxanthin and derivatives of this compound were isolated from a variety of environmental samples. phylogenetic analysis showed that these strains grouped with different clusters of erwinia type strains. four strains representing the phylogenetic diversity were chosen for further characterization, which revealed their genetic diversity as well as their biochemical diversity. the carotenoid synthesis gene clusters cloned from the four strains had thre ...200516332796
isolation and characterization of microorganisms associated with the traditional sorghum fermentation for production of sudanese kisra.sorghum flour obtained from sudan was mixed with water in a 1:2 (wt/vol) ratio and fermented at 30 degrees c for 24 h. the bacterial populations increased with fermentation time and reached a plateau at approximately 18 h. at the end of 24 h, sorghum batter ph had dropped from 5.95 to 3.95 and the batter had a lactic acid content of 0.80%. the microbial population during the 24 h of fermentation consisted of bacteria (pediococcus pentosaceus, lactobacillus confusus, lactobacillus brevis, lactoba ...199116348551
cloning and expression of a xylitol-4-dehydrogenase gene from pantoea ananatis.the pantoea ananatis atcc 43072 mutant strain is capable of growing with xylitol as the sole carbon source. the xylitol-4-dehydrogenase (xdh) catalyzing the oxidation of xylitol to l-xylulose was isolated from the cell extract of this strain. the n-terminal amino acid sequence of the purified protein was determined, and an oligonucleotide deduced from this peptide sequence was used to isolate the xylitol-4-dehydrogenase gene (xdh) from a p. ananatis gene library. nucleotide sequence analysis rev ...200616391066
biosynthesis of novel carotenoid families based on unnatural carbon backbones: a model for diversification of natural product pathways.we show that the c40 carotenoid desaturase crti from pantoea ananatis (erwinia uredovora) is capable of desaturating unnaturally long c45 and c50 carotenoid backbones in recombinant e. coli. desaturation step number in these pathways is not very specific, and at least ten new c45 and c50 carotenoids were synthesized. we also present evidence for a novel asymmetric c40 backbone formed by the condensation of farnesyl diphosphate (c15pp) with farnesylgeranyl diphosphate (c25pp), and the subsequent ...200616478677
exploring the potential of the bacterial carotene desaturase crti to increase the beta-carotene content in golden rice.to increase the beta-carotene (provitamin a) content and thus the nutritional value of golden rice, the optimization of the enzymes employed, phytoene synthase (psy) and the erwinia uredovora carotene desaturase (crti), must be considered. crti was chosen for this study because this bacterial enzyme, unlike phytoene synthase, was expressed at barely detectable levels in the endosperm of the golden rice events investigated. the low protein amounts observed may be caused by either weak cauliflower ...200616488912
maize cdnas expressed in endosperm encode functional farnesyl diphosphate synthase with geranylgeranyl diphosphate synthase activity.isoprenoids are the most diverse and abundant group of natural products. in plants, farnesyl diphosphate (fpp) and geranylgeranyl diphosphate (ggpp) are precursors to many isoprenoids having essential functions. terpenoids and sterols are derived from fpp, whereas gibberellins, carotenoids, casbenes, taxenes, and others originate from ggpp. the corresponding synthases (fpp synthase [fpps] and ggpp synthase [ggpps]) catalyze, respectively, the addition of two and three isopentenyl diphosphate mol ...200616581875
characterization of bacterial beta-carotene 3,3'-hydroxylases, crtz, and p450 in astaxanthin biosynthetic pathway and adonirubin production by gene combination in escherichia coli.beta-carotene hydroxylase (crtz) is one of rate-limiting enzymes for astaxanthin production. a complementation analysis was conducted using escherichia coli transformants to compare the catalytic efficiency of bacterial crtz from brevundimonas sp. sd212, paracoccus sp. pc1 (formerly known as alcaligenes sp. pc-1), paracoccus sp. n81106 (agrobacterium aurantiacum), pantoea ananatis (erwinia uredovora 20d3), marine bacterium p99-3, and p450 monooxygenase (cyp175a1) from thermus thermophilus hb27. ...200616614859
changes in the spoilage-related microbiota of beef during refrigerated storage under different packaging conditions.the microbial spoilage of beef was monitored during storage at 5 degrees c under three different conditions of modified-atmosphere packaging (map): (i) air (map1), (ii) 60% o2 and 40% co2 (map2), and (iii) 20% o2 and 40% co2 (map3). pseudomonas, enterobacteriaceae, brochothrix thermosphacta, and lactic acid bacteria were monitored by viable counts and pcr-denaturing gradient gel electrophoresis (dgge) analysis during 14 days of storage. moreover, headspace gas composition, weight loss, and beef ...200616820458
culturable leaf-associated bacteria on tomato plants and their potential as biological control agents.culturable leaf-associated bacteria inhabiting a plant have been considered as promising biological control agent (bca) candidates because they can survive on the plant. we investigated the relationship between bacterial groups of culturable leaf-associated bacteria on greenhouse- and field-grown tomato leaves and their antifungal activities against tomato diseases in vitro and in vivo. in addition, the isolated bacteria were analyzed for n-acyl-homoserine lactone (ahl) and indole-3-acetic acid ...200717356949
metabolic engineering of potato carotenoid content through tuber-specific overexpression of a bacterial mini-pathway.since the creation of "golden rice", biofortification of plant-derived foods is a promising strategy for the alleviation of nutritional deficiencies. potato is the most important staple food for mankind after the cereals rice, wheat and maize, and is extremely poor in provitamin a carotenoids.200717406674
identification and functional analysis of a phytoene desaturase gene from the extremely radioresistant bacterium deinococcus radiodurans.the phytoene-related desaturases are the key enzymes in the carotenoid biosynthetic pathway. the gene encoding phytoene desaturase in the deinoxanthin synthesis pathway of deinococcus radiodurans was identified and characterized. two putative phytoene desaturase homologues (dr0861 and dr0810) were identified by analysis of conserved amino acid regions, and the former displayed the highest identity (68 %) with phytoene desaturase of the cyanobacterium gloeobacter violaceus. dr0861 gene knockout a ...200717464079
[effects of a lactic acid bacteria community sfc-2 treated on rice straw].aimed to utilize rice straw and lessen the pressure of environment, the rice straw was used as the fermentation material, and a lactic acid bacteria community sfc-2 from my laboratory was inoculated into the rice straw to investigate the inoculation effects. after 30 days fermentation, the inoculated fermented straw smelt acid-fragrant, and the ph value was 3.8, which was lower than the control of 4.1. furthermore, lactic acid concentration was more than that in the control. especially l-lactic ...200717674756
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