| localization of ds-transposon containing t-dna inserts in the diploid transgenic potato: linkage to the r1 resistance gene against phytophthora infestans (mont.) de bary. | the dissociation transposable element (ds) of maize containing nptii was introduced into the diploid potato (solanum tuberosum) clone j91-6400-a16 through agrobacterium tumefaciens mediated transformation. genomic dna sequences flanking the t-dnas from 312 transformants were obtained with inverse polymerase chain reaction or plasmid rescue techniques and used as probes for rflp linkage analysis. the rflp map location of 60 t-dnas carrying ds-nptii was determined. the t-dna distribution per chrom ... | 1996 | 18469890 |
| agrobacterium-mediated transformation of large-flowered purslane (portulaca grandiflora h.). | transformation of portulaca grandiflora has been developed with agrobacterium tumefaciens strains a281 and t1272. transformation was assessed by the following criteria: selection of hormone independent callus, antibiotic-resistant callus, and transgenic antibiotic-resistant plants. in addition, dna hybridization analysis demonstrated that the dna from tumor lines contained sequences homologous to binary vector t-dna of strain a281. following transformation with strain t1272, segregation analysis ... | 1995 | 18470202 |
| triad pattern algorithm for predicting strong promoter candidates in bacterial genomes. | bacterial promoters, which increase the efficiency of gene expression, differ from other promoters by several characteristics. this difference, not yet widely exploited in bioinformatics, looks promising for the development of relevant computational tools to search for strong promoters in bacterial genomes. | 2008 | 18471287 |
| transgenic superroots of lotus corniculatus can be regenerated from superroot-derived leaves following agrobacterium-mediated transformation. | super-growing roots (superroots; sr), which have been established in the legume species lotus corniculatus, are a fast-growing root culture that allows continuous root cloning, direct somatic embryogenesis and mass regeneration of plants under entirely growth regulator-free culture conditions. these features are unique for non-hairy root cultures, and they are now stably expressed since the culture was isolated more than 10 years ago (1997). attempts to achieve direct and stable transformation o ... | 2008 | 18471930 |
| pbinplus/ars: an improved plant transformation vector based on pbinplus. | binary plant transformation vectors are widely used for introduction of transgenes into plants via agrobacterium tumefaciens-mediated transformation. we report the construction of a binary plant vector pbinplus/ars based on the pbinplus vector. improvements introduced into pbinplus/ars include the use of nonproprietary (ubiquitin-3 gene of solanum tuberosum) promoter and terminator sequences for transcription of the nptii selectable marker and introduction of rare 8-bp restriction enzyme sites f ... | 2008 | 18476828 |
| terminal proteins of streptomyces chromosome can target dna into eukaryotic nuclei. | streptomyces species are highly abundant soil bacteria that possess linear chromosomes (and linear plasmids). the 5' ends of these molecules are covalently bound by terminal proteins (tps), that are important for integrity and replication of the telomeres. there are at least two types of tps, both of which contain a dna-binding domain and a classical eukaryotic nuclear localization signal (nls). here we show that the nls motifs on these tps are highly efficient in targeting the proteins along wi ... | 2008 | 18480119 |
| flower-specific expression of the agrobacterium tumefaciens isopentenyltransferase gene results in radial expansion of floral organs in petunia hybrida. | summary: biotechnology has the potential to modify commercially important traits of crops, such as fruit size and stress tolerance. to date, the floricultural industry has not profited significantly from these possibilities to manipulate, for example, flower size. cytokinins are known to be involved in many aspects of plant development, including cell division. increasing the amount of cytokinins has the potential to increase the size of an organ, such as the flower or the fruit. the agrobacteri ... | 2008 | 18482222 |
| peptidoglycan and muropeptides from pathogens agrobacterium and xanthomonas elicit plant innate immunity: structure and activity. | peptidoglycan (pgn) is a unique and essential structural part of the bacterial cell wall. pgns from two contrasting gram-negative plant pathogenic bacteria elicited components characteristic of the innate immune system in arabidopsis thaliana, such as transcription of the defense gene pr1, oxidative burst, medium alkalinization, and formation of callose. highly purified muropeptides from pgns were more effective elicitors of early defense responses than native pgn. therefore, pgn and its constit ... | 2008 | 18482696 |
| an ompa family protein, a target of the gini/ginr quorum-sensing system in gluconacetobacter intermedius, controls acetic acid fermentation. | via n-acylhomoserine lactones, the gini/ginr quorum-sensing system in gluconacetobacter intermedius nci1051, a gram-negative acetic acid bacterium, represses acetic acid and gluconic acid fermentation. two-dimensional polyacrylamide gel electrophoretic analysis of protein profiles of strain nci1051 and gini and ginr mutants identified a protein that was produced in response to the gini/ginr regulatory system. cloning and nucleotide sequencing of the gene encoding this protein revealed that it en ... | 2008 | 18487322 |
| symbiosis-promoting and deleterious effects of nopt, a novel type 3 effector of rhizobium sp. strain ngr234. | establishment of symbiosis between certain host plants and nitrogen-fixing bacteria ("rhizobia") depends on type 3 effector proteins secreted via the bacterial type 3 secretion system (t3ss). here, we report that the open reading frame y4zc of strain ngr234 encodes a novel rhizobial type 3 effector, termed nopt (for nodulation outer protein t). analysis of secreted proteins from ngr234 and t3ss mutants revealed that nopt is secreted via the t3ss. nopt possessed autoproteolytic activity when expr ... | 2008 | 18487326 |
| functional characterization and localization of the tcph conjugation protein from clostridium perfringens. | in clostridium perfringens, conjugative plasmids encode important virulence factors, such as toxins and resistance determinants. all of these plasmids carry a conjugation locus that consists of 11 genes: intp and tcpa to tcpj. three proteins, tcpa, a potential coupling protein, tcpf, a putative atpase that is similar to orf15 from tn916, and tcph, which contains virb6-like domains, are essential for conjugation in the prototype conjugative plasmid pcw3. to analyze the functional domains of tcph, ... | 2008 | 18487333 |
| genes and enzymes of azetidine-2-carboxylate metabolism: detoxification and assimilation of an antibiotic. | l-(-)-azetidine-2-carboxylate (ac) is a toxic, natural product analog of l-proline. this study revealed the genes and biochemical strategy employed by pseudomonas sp. strain a2c to detoxify and assimilate ac as its sole nitrogen source. the gene region from pseudomonas sp. strain a2c required for detoxification was cloned into escherichia coli and sequenced. the 7.0-kb region contained eight identifiable genes. four encoded putative transporters or permeases for gamma-amino acids or drugs. anoth ... | 2008 | 18487339 |
| infection-associated type iv secretion systems of bartonella and their diverse roles in host cell interaction. | type iv secretion systems (t4sss) are transporters of gram-negative bacteria that mediate interbacterial dna transfer, and translocation of virulence factors into eukaryotic host cells. the alpha-proteobacterial genus bartonella comprises arthropod-borne pathogens that colonize endothelial cells and erythrocytes of their mammalian reservoir hosts, thereby causing long-lasting intraerythrocytic infections. the deadly human pathogen bartonella bacilliformis holds an isolated position in the barton ... | 2008 | 18489724 |
| viable chimaeric viruses confirm the biological importance of sequence specific maize streak virus movement protein and coat protein interactions. | a variety of interactions between up to three different movement proteins (mps), the coat protein (cp) and genomic dna mediate the inter- and intra-cellular movement of geminiviruses in the genus begomovirus. although movement of viruses in the genus mastrevirus is less well characterized, direct interactions between a single mp and the cp of these viruses is also clearly involved in both intra- and intercellular trafficking of virus genomic dna. however, it is currently unknown how specific the ... | 2008 | 18489800 |
| formation of enantiopure 5-substituted oxazolidinones through enzyme-catalysed kinetic resolution of epoxides. | halohydrin dehalogenase from agrobacterium radiobacter catalyzed the enantioselective ring opening of terminal epoxides with cyanate as a nucleophile, yielding 5-substituted oxazolidinones in high yields and with high enantiopurity (69-98% ee). this is the first example of the biocatalytic conversion of a range of epoxides to the corresponding oxazolidinones. | 2008 | 18491860 |
| the effect of chromosome geometry on genetic diversity. | although organisms with linear chromosomes must solve the problem of fully replicating their chromosome ends, this chromosome configuration has emerged repeatedly during bacterial evolution and is evident in three divergent bacterial phyla. the benefit usually ascribed to this topology is the ability to boost genetic variation through increased recombination. but because numerous processes can impact linkage disequilibrium, such an effect is difficult to assess by comparing across bacterial taxa ... | 2008 | 18493068 |
| agrobacterium-mediated genetic transformation of prunus salicina. | we report agrobacterium tumefaciens-mediated transformation of two prunus salicina varieties, 'angeleno' and 'larry anne', using a modification of the hypocotyl slice technique previously described for p. domestica. regeneration rates on thidiazuron (tdz) and indole-3-butyric acid (iba) supplemented murashige and skoog (ms) media reached 11% for 'angeleno' and 19% for 'larry anne' hypocotyl slices. transformation using agrobacterium tumefaciens gv3101 harboring a plasmid with the neomycin phosph ... | 2008 | 18493725 |
| transposon mediation allows a symbiotic plasmid of rhizobium leguminosarum bv. trifolii to become a symbiosis island in agrobacterium and rhizobium. | the symbiotic plasmid (psym) of rhizobium leguminosarum bv. trifolii 4s5, which carries tn5-mob, was successfully transferred into agrobacterium tumefaciens a136 by using a conjugation method. the resulting transconjugants induced the development of ineffective nitrogen-fixing nodules on the roots of white clover seedlings. depending on the manner in which the psym was retained, the transconjugants were divided into two groups of strains, afp and afcs. psym was retained as a plasmid in the afp s ... | 2008 | 18497485 |
| hairpin-mediated down-regulation of the urea cycle enzyme argininosuccinate lyase in agaricus bisporus. | a double-stranded (ds) rna hairpin-mediated down-regulation system was developed for the cultivated mushroom agaricus bisporus, and the role of the urea cycle enzyme argininosuccinate lyase (asl) in mushroom post-harvest development was investigated. hairpin expression vectors were constructed to initiate down-regulation of asl and introduced into a. bisporus by agrobacterium tumefaciens-mediated transformation. transcripts of asl were significantly reduced (93.1 and 99.9%) in two transformants ... | 2008 | 18499425 |
| transient expression of chicken alpha interferon gene in lettuce. | we investigated the possibility of producing chicken alpha interferon (chifn-alpha) in transgenic plants. the cdna encoding chifn-alpha was introduced into lettuce (lactuca sativa l.) plants by using an agro-infiltration transient expression system. the chifn-alpha gene was correctly transcribed and translated in the lettuce plants according to rt-pcr and elisa assays. recombinant protein exhibited antiviral activity in vitro by inhibition of vesicular stomatitis virus (vsv) replication on chick ... | 2008 | 18500773 |
| dynamics of arabidopsis dynamin-related protein 1c and a clathrin light chain at the plasma membrane. | plant morphogenesis depends on polarized exocytic and endocytic membrane trafficking. members of the arabidopsis thaliana dynamin-related protein 1 (drp1) subfamily are required for polarized cell expansion and cytokinesis. using a combination of live-cell imaging techniques, we show that a functional drp1c green fluorescent fusion protein (drp1c-gfp) was localized at the division plane in dividing cells and to the plasma membrane in expanding interphase cells. in both tip growing root hairs and ... | 2008 | 18502847 |
| genetic and functional characterization of the type iv secretion system in wolbachia. | a type iv secretion system (t4ss) is used by many symbiotic and pathogenic intracellular bacteria for the successful infection of and survival, proliferation, and persistence within hosts. in this study, the presence and function of the t4ss in wolbachia strains were investigated by a combination of genetic screening and immunofluorescence microscopy. two operons of virb-vird4 loci were found in the genome of wolbachia pipientis strain watab3, from the hymenoptera asobara tabida, and strain wri, ... | 2008 | 18502862 |
| agrobacterium-mediated disruption of a nonribosomal peptide synthetase gene in the invertebrate pathogen metarhizium anisopliae reveals a peptide spore factor. | numerous secondary metabolites have been isolated from the insect pathogenic fungus metarhizium anisopliae, but the roles of these compounds as virulence factors in disease development are poorly understood. we targeted for disruption by agrobacterium tumefaciens-mediated transformation a putative nonribosomal peptide synthetase (nps) gene, manps1. four of six gene disruption mutants identified were examined further. chemical analyses showed the presence of serinocyclins, cyclic heptapeptides, i ... | 2008 | 18502925 |
| rna interference-mediated repression of cell wall invertase impairs defense in source leaves of tobacco. | the significance of cell wall invertase (cwinv) for plant defense was investigated by comparing wild-type tobacco (nicotiana tabacum) samsun nn (snn) with plants with rna interference (rnai)-mediated repression of cwinv (snncwinv). in source leaves of snncwinv, the activity of cwinv was repressed by about 90%. sucrose export and apoplastic carbohydrate levels were significantly reduced, while photosynthesis and dark respiration exhibited little or no change. activities of sucrose synthase and ph ... | 2008 | 18502974 |
| mta is an arabidopsis messenger rna adenosine methylase and interacts with a homolog of a sex-specific splicing factor. | n6-methyladenosine is a ubiquitous modification identified in the mrna of numerous eukaryotes, where it is present within both coding and noncoding regions. however, this base modification does not alter the coding capacity, and its biological significance remains unclear. we show that arabidopsis thaliana mrna contains n6-methyladenosine at levels similar to those previously reported for animal cells. we further show that inactivation of the arabidopsis ortholog of the yeast and human mrna aden ... | 2008 | 18505803 |
| susceptibility of local agrobacterium tumefaciens strains to streptomycetes isolates from jordan soils. | five strains of agrobacterium tumefaciens were isolated and characterized from 12 different plant tumors. the susceptibility of these phytopathogens to antibiotics and to soil streptomyces isolates was tested. among the 90 streptomyces isolates, only 12 were able to inhibit the growth of at least one a. tumefaciens strain. four strains of a. tumefaciens were susceptible to streptomycin and cefotaxime. in addition, streptomyces 404 strain was able to inhibit the growth of four strains of the agro ... | 2008 | 18506907 |
| inquilinus limosus and cystic fibrosis. | | 2008 | 18507928 |
| the whole-genome sequencing of the obligate intracellular bacterium orientia tsutsugamushi revealed massive gene amplification during reductive genome evolution. | scrub typhus ('tsutsugamushi' disease in japanese) is a mite-borne infectious disease. the causative agent is orientia tsutsugamushi, an obligate intracellular bacterium belonging to the family rickettsiaceae of the subdivision alpha-proteobacteria. in this study, we determined the complete genome sequence of o. tsutsugamushi strain ikeda, which comprises a single chromosome of 2 008 987 bp and contains 1967 protein coding sequences (cdss). the chromosome is much larger than those of other membe ... | 2008 | 18508905 |
| citrus genomics. | citrus is one of the most widespread fruit crops globally, with great economic and health value. it is among the most difficult plants to improve through traditional breeding approaches. currently, there is risk of devastation by diseases threatening to limit production and future availability to the human population. as technologies rapidly advance in genomic science, they are quickly adapted to address the biological challenges of the citrus plant system and the world's industries. the histori ... | 2008 | 18509486 |
| life-cycle and genome of otv5, a large dna virus of the pelagic marine unicellular green alga ostreococcus tauri. | large dna viruses are ubiquitous, infecting diverse organisms ranging from algae to man, and have probably evolved from an ancient common ancestor. in aquatic environments, such algal viruses control blooms and shape the evolution of biodiversity in phytoplankton, but little is known about their biological functions. we show that ostreococcus tauri, the smallest known marine photosynthetic eukaryote, whose genome is completely characterized, is a host for large dna viruses, and present an analys ... | 2008 | 18509524 |
| competitive and cooperative effects in quorum-sensing-regulated galactoglucan biosynthesis in sinorhizobium meliloti. | the symbiotic nitrogen-fixing bacterium sinorhizobium meliloti possesses the sin quorum-sensing system based on n-acyl homoserine lactones (ahls) as signal molecules. the sin system consists of sini, the ahl synthase, and sinr, the luxr-type regulator. this system regulates the expression of a multitude of s. meliloti genes through expr, another luxr-type regulator. analysis of the activity of the sini promoter showed that the expression of sini is dependent on sinr and enhanced by a combination ... | 2008 | 18515420 |
| mapk signaling regulates nitric oxide and nadph oxidase-dependent oxidative bursts in nicotiana benthamiana. | nitric oxide (no) and reactive oxygen species (ros) act as signals in innate immunity in plants. the radical burst is induced by inf1 elicitin, produced by the oomycete pathogen phytophthora infestans. no associated1 (noa1) and nadph oxidase participate in the radical burst. here, we show that mitogen-activated protein kinase (mapk) cascades mek2-sipk/ntf4 and mek1-ntf6 participate in the regulation of the radical burst. no generation was induced by conditional activation of sipk/ntf4, but not b ... | 2008 | 18515503 |
| genetically modified plants and human health. | genetically modified (or gm) plants have attracted a large amount of media attention in recent years and continue to do so. despite this, the general public remains largely unaware of what a gm plant actually is or what advantages and disadvantages the technology has to offer, particularly with regard to the range of applications for which they can be used. from the first generation of gm crops, two main areas of concern have emerged, namely risk to the environment and risk to human health. as g ... | 2008 | 18515776 |
| transformation by t-dna integration causes highly sterile phenotype independent of transgenes in arabidopsis thaliana. | agrobacterium tumefaciens-mediated gene transformation caused highly sterile phenotype in t1 transgenic populations of arabidopsis thaliana. the phenomenon occurred independent of the genes and construct types used for transformation. the occurring frequency is less than 10% and the phenotype is inheritable. intensive examination elucidated that the sterility is due to indehiscence or delayed dehiscence of the anthers during the flowering stage, resulting from the reduced or disordered endotheci ... | 2008 | 18521611 |
| the genome of the versatile nitrogen fixer azorhizobium caulinodans ors571. | biological nitrogen fixation is a prokaryotic process that plays an essential role in the global nitrogen cycle. azorhizobium caulinodans ors571 has the dual capacity to fix nitrogen both as free-living organism and in a symbiotic interaction with sesbania rostrata. the host is a fast-growing, submergence-tolerant tropical legume on which a. caulinodans can efficiently induce nodule formation on the root system and on adventitious rootlets located on the stem. | 2008 | 18522759 |
| agrobacterium tumefaciens-induced bacteraemia does not lead to reporter gene expression in mouse organs. | agrobacterium tumefaciens is the main plant biotechnology gene transfer tool with host range which can be extended to non-plant eukaryotic organisms under laboratory conditions. known medical cases of agrobacterium species isolation from bloodstream infections necessitate the assessment of biosafety-related risks of a. tumefaciens encounters with mammalian organisms. here, we studied the survival of a. tumefaciens in bloodstream of mice injected with bacterial cultures. bacterial titers of 10(8) ... | 2008 | 18523638 |
| expression of insect (microdera puntipennis dzungarica) antifreeze protein mpafp149 confers the cold tolerance to transgenic tobacco. | to elucidate the function of antifreeze protein from microdera puntipennis dzhungarica for freezing stress tolerance in plant, the construct of mpafp149 gene with the signal peptide sequence responsible for secreting the native mpafp149 into the apoplast space under control of a cauliflower mosaic virus 35s promoter was introduced into tobacco by agrobacterium tumefaciens-mediated transformation. the observation of immunogold localization by tem (transmission electron microscope) showed that the ... | 2008 | 18528694 |
| a versatile assay for the identification of rna silencing suppressors based on complementation of viral movement. | the cell-to-cell movement of turnip crinkle virus (tcv) in nicotiana benthamiana requires the presence of its coat protein (cp), a known suppressor of rna silencing. rna transcripts of a tcv construct containing a reporter gene (green fluorescent protein) (tcv-sgfp) in place of the cp open reading frame generated foci of three to five cells. tcv cp delivered in trans by agrobacterium tumefaciens infiltration potentiated movement of tcv-sgfp and increased foci diameter, on average, by a factor of ... | 2008 | 18533829 |
| highly plastic genome of microcystis aeruginosa pcc 7806, a ubiquitous toxic freshwater cyanobacterium. | the colonial cyanobacterium microcystis proliferates in a wide range of freshwater ecosystems and is exposed to changing environmental factors during its life cycle. microcystis blooms are often toxic, potentially fatal to animals and humans, and may cause environmental problems. there has been little investigation of the genomics of these cyanobacteria. | 2008 | 18534010 |
| structure, function, and evolution of bacterial atp-binding cassette systems. | summary: atp-binding cassette (abc) systems are universally distributed among living organisms and function in many different aspects of bacterial physiology. abc transporters are best known for their role in the import of essential nutrients and the export of toxic molecules, but they can also mediate the transport of many other physiological substrates. in a classical transport reaction, two highly conserved atp-binding domains or subunits couple the binding/hydrolysis of atp to the translocat ... | 2008 | 18535149 |
| coat protein-mediated resistance against an indian isolate of the cucumber mosaic virus subgroup ib in nicotiana benthamiana. | coat protein (cp) -mediated resistance against an indian isolate of the cucumber mosaic virus (cmv) subgroup ib was demonstrated in transgenic lines of nicotiana benthamiana through agrobacterium tumefaciens-mediated transformation. out of the fourteen independently transformed lines developed, two lines were tested for resistance against cmv by challenge inoculations. the transgenic lines exhibiting complete resistance remained symptomless throughout life and showed reduced or no virus accumula ... | 2008 | 18535359 |
| methylation of chloroplast dna does not affect viability and maternal inheritance in tobacco and may provide a strategy towards transgene containment. | we report the integration of a type ii restriction-methylase, mfoki, into the tobacco chloroplast genome and we demonstrate that the introduced enzyme effectively directs the methylation of its target sequence in vivo and does not affect maternal inheritance. we further report the transformation of tobacco with an e. coli dcm methylase targeted to plastids and we demonstrate efficient cytosine methylation of the plastid genome. both adenosine methylation of foki sites and cytosine methylation of ... | 2008 | 18536921 |
| the lmpma1 gene of leptosphaeria maculans encodes a plasma membrane h+-atpase isoform essential for pathogenicity towards oilseed rape. | following agrobacterium tumefaciens-mediated mutagenesis in leptosphaeria maculans, we identified the mutant 210, displaying total loss of pathogenicity towards its host plant (brassica napus). microscopic observations showed that m210 is unable to germinate on the host leaf surface and is thus blocked at the pre-penetration stage. the pathogenicity phenotype is linked with a single t-dna insertion into the promoter region of a typical plasma membrane h(+)-atpase-encoding gene, termed lmpma1, th ... | 2008 | 18538267 |
| helicobacter hepaticus hhgi1 is a pathogenicity island associated with typhlocolitis in b6.129-il10 tm1cgn mice. | helicobacter hepaticus strain 3b1 (h. hepaticus) contains a genomic island of approximately 71 kb, hhgi1, with some of the common features shared among known bacterial pathogenicity islands. in this study, we characterized the pathogenic potential of hhgi1 by infecting b6.129-il10 tm1cgn (il10-/-) mice with an isogenic mutant (namely hhpaid1) lacking 19 predicted genes within hhgi1. in contrast to h. hepaticus (p<0.001), hhpaid1 did not cause typhlocolitis and hyperplasia in il10-/- mice. coloni ... | 2008 | 18538610 |
| agrobacterium radiobacter bacteremia in oncologic and geriatric patients: presentation of two cases and review of the literature. | we report here two cases of agrobacterium radiobacter bacteremia. these cases were observed at the same institution over a short time period (3 months). | 2008 | 18539494 |
| inhibition of 3' modification of small rnas in virus-infected plants require spatial and temporal co-expression of small rnas and viral silencing-suppressor proteins. | plant viruses are inducers and targets of rna silencing. viruses counteract with rna silencing by expressing silencing-suppressor proteins. many of the identified proteins bind sirnas, which prevents assembly of silencing effector complexes, and also interfere with their 3' methylation, which protects them against degradation. here, we investigated the 3' modification of silencing-related small rnas in nicotiana benthamiana plants infected with viruses expressing rna silencing suppressors, the p ... | 2008 | 18539609 |
| atpase activity and oligomeric state of trwk, the virb4 homologue of the plasmid r388 type iv secretion system. | type iv secretion systems (t4ss) mediate the transfer of dna and protein substrates to target cells. trwk, encoded by the conjugative plasmid r388, is a member of the virb4 family, comprising the largest and most conserved proteins of t4ss. virb4 was suggested to be an atpase involved in energizing pilus assembly and substrate transport. however, conflicting experimental evidence concerning virb4 atp hydrolase activity was reported. here, we demonstrate that trwk is able to hydrolyze atp in vitr ... | 2008 | 18539740 |
| a class i adp-ribosylation factor gtpase-activating protein is critical for maintaining directional root hair growth in arabidopsis. | membrane trafficking and cytoskeletal dynamics are important cellular processes that drive tip growth in root hairs. these processes interact with a multitude of signaling pathways that allow for the efficient transfer of information to specify the direction in which tip growth occurs. here, we show that agd1, a class i adp ribosylation factor gtpase-activating protein, is important for maintaining straight growth in arabidopsis (arabidopsis thaliana) root hairs, since mutations in the agd1 gene ... | 2008 | 18539780 |
| the transcription factor vvmyb5b contributes to the regulation of anthocyanin and proanthocyanidin biosynthesis in developing grape berries. | among the dramatic changes occurring during grape berry (vitis vinifera) development, those affecting the flavonoid pathway have provoked a number of investigations in the last 10 years. in addition to producing several compounds involved in the protection of the berry and the dissemination of the seeds, final products of this pathway also play a critical role in berry and wine quality. in this article, we describe the cloning and functional characterization of vvmyb5b, a cdna isolated from a gr ... | 2008 | 18539781 |
| structure of a trypanosoma brucei alpha/beta-hydrolase fold protein with unknown function. | the structure of a structural genomics target protein, tbru020260aaa from trypanosoma brucei, has been determined to a resolution of 2.2 a using multiple-wavelength anomalous diffraction at the se k edge. this protein belongs to pfam sequence family pf08538 and is only distantly related to previously studied members of the alpha/beta-hydrolase fold family. structural superposition onto representative alpha/beta-hydrolase fold proteins of known function indicates that a possible catalytic nucleop ... | 2008 | 18540054 |
| diversity of bacillus-like organisms isolated from deep-sea hypersaline anoxic sediments. | the deep-sea, hypersaline anoxic brine lakes in the mediterranean are among the most extreme environments on earth, and in one of them, the mgcl2-rich discovery basin, the presence of active microbes is equivocal. however, thriving microbial communities have been detected especially in the chemocline between deep seawater and three nacl-rich brine lakes, l'atalante, bannock and urania. by contrast, the microbiota of these brine-lake sediments remains largely unexplored. | 2008 | 18541011 |
| regeneration of transgenic cryptomeria japonica d. don after agrobacterium tumefaciens-mediated transformation of embryogenic tissue. | a genetic transformation procedure for cryptomeria japonica was developed after co-cultivation of embryogenic tissues with the disarmed agrobacterium tumefaciens strain c58/pmp90, which harbours the visual reporter gene sgfp and two selectable marker genes, hpt and nptii. we were able to generate eight and three independent transgenic lines per gram of embryogenic tissue after selection on hygromycin and kanamycin medium, respectively. transgenic plants were regenerated through somatic embryogen ... | 2008 | 18542965 |
| an intensive understanding of vacuum infiltration transformation of pakchoi (brassica rapa ssp. chinensis). | pakchoi (brassica rapa l. ssp. chinensis), a kind of chinese cabbage, is an important vegetable in asian countries. agrobacterium mediated in planta vacuum infiltration transformation has been performed in pakchoi since 1998, but a detailed study on this technique was lacking. pakchoi plants 40-50 days old with inflorescences were vacuum infiltrated with agrobacterium tumefaciens strain c58c1 harboring the binary vector pbbbast-gus-intron. the transformation frequency in the harvested seeds main ... | 2008 | 18542966 |
| construction of an infectious full-length cdna clone of potato virus m. | an infectious full-length cdna clone of potato virus m (pvm) was produced. total rna was extracted from pvm-infected nicotiana hesperis plants and used for cdna synthesis. subsequent rt-pcr produced two dna fragments of about 5.5 and 3.2 kbp, which were ligated downstream of an enhanced 35s cauliflower mosaic virus promoter. after cloning of the enhanced 35s promoter with the pvm sequence into a modified pbin19 plasmid and electroporation of agrobacterium tumefaciens, the agroinoculated pvm full ... | 2008 | 18543062 |
| deciphering the ubiquitin-mediated pathway in apicomplexan parasites: a potential strategy to interfere with parasite virulence. | reversible modification of proteins through the attachment of ubiquitin or ubiquitin-like modifiers is an essential post-translational regulatory mechanism in eukaryotes. the conjugation of ubiquitin or ubiquitin-like proteins has been demonstrated to play roles in growth, adaptation and homeostasis in all eukaryotes, with perturbation of ubiquitin-mediated systems associated with the pathogenesis of many human diseases, including cancer and neurodegenerative disorders. | 2008 | 18545708 |
| the expression of analgesic-antitumor peptide (agap) from chinese buthus martensii karsch in transgenic tobacco and tomato. | the present study aimed to obtain analgesic-antitumor peptide (agap) gene expression in plants. the analgesic-antitumor peptide (agap) gene was from the venom of buthus martensii karsch. previous studies showed that agap has both analgesic and antitumor activities, suggesting that agap would be useful in clinical situations as an antitumor drug. given that using a plant as an expression vector has more advantages than prokaryotic expression, we tried to obtain transgenic plants containing agap. ... | 2009 | 18546060 |
| a critical role of two positively charged amino acids in the jas motif of arabidopsis jaz proteins in mediating coronatine- and jasmonoyl isoleucine-dependent interactions with the coi1 f-box protein. | summary: coronatine is an important virulence factor produced by several pathovars of the bacterial pathogen pseudomonas syringae. the structure of coronatine is similar to that of a class of plant hormones called jasmonates (jas). an important step in ja signaling is the scf(coi1) e3 ubiquitin ligase-dependent degradation of jaz repressor proteins. we have recently shown that jasmonoyl isoleucine (ja-ile) promotes physical interaction between arabidopsis jaz1 and coi1 (the f-box component of sc ... | 2008 | 18547396 |
| type iv secretion systems: tools of bacterial horizontal gene transfer and virulence. | type iv secretion systems (t4sss) are multisubunit cell-envelope-spanning structures, ancestrally related to bacterial conjugation machines, which transfer proteins and nucleoprotein complexes across membranes. t4sss mediate horizontal gene transfer, thus contributing to genome plasticity and the evolution of pathogens through dissemination of antibiotic resistance and virulence genes. moreover, t4sss are also used for the delivery of bacterial effector proteins across the bacterial membrane and ... | 2008 | 18549454 |
| investigation of heavy metal hyperaccumulation at the cellular level: development and characterization of thlaspi caerulescens suspension cell lines. | the ability of thlaspi caerulescens, a zinc (zn)/cadmium (cd) hyperaccumulator, to accumulate extremely high foliar concentrations of toxic heavy metals requires coordination of uptake, transport, and sequestration to avoid damage to the photosynthetic machinery. the study of these metal hyperaccumulation processes at the cellular level in t. caerulescens has been hampered by the lack of a cellular system that mimics the whole plant, is easily transformable, and competent for longer term studies ... | 2008 | 18550685 |
| isomaltose production by modification of the fructose-binding site on the basis of the predicted structure of sucrose isomerase from "protaminobacter rubrum". | "protaminobacter rubrum" sucrose isomerase (si) catalyzes the isomerization of sucrose to isomaltulose and trehalulose. si catalyzes the hydrolysis of the glycosidic bond with retention of the anomeric configuration via a mechanism that involves a covalent glycosyl enzyme intermediate. it possesses a (325)rldrd(329) motif, which is highly conserved and plays an important role in fructose binding. the predicted three-dimensional active-site structure of si was superimposed on and compared with th ... | 2008 | 18552181 |
| sequencing and expression of two arsenic resistance operons with different functions in the highly arsenic-resistant strain ochrobactrum tritici scii24t. | arsenic (as) is a natural metalloid, widely used in anthropogenic activities, that can exist in different oxidation states. throughout the world, there are several environments contaminated with high amounts of arsenic where many organisms can survive. the most stable arsenical species are arsenate and arsenite that can be subject to chemically and microbiologically oxidation, reduction and methylation reactions. organisms surviving in arsenic contaminated environments can have a diversity of me ... | 2008 | 18554386 |
| agrobacterium tumefaciens-mediated transformation as a tool for insertional mutagenesis in the fungus penicillium marneffei. | penicillium marneffei is an opportunistic fungal pathogen of humans, causing respiratory, skin, and systemic mycosis in south-east asia. here we describe the transformation of p. marneffei with agrobacterium tumefaciens, and the optimization of the transformation procedure. transformations in different combinations between a. tumefaciens stains (lba4404 and eha105) and binary vectors (pcb309a, pbi129a, and pcambia1312a) showed that eha105/pbi129a were the most efficient partners. southern blot a ... | 2008 | 18555677 |
| [agrobacterium tumefaciens-mediated transformation of uracil auxotroph aspergillus fumigatus is an efficient method for target gene knockout]. | to investigate the efficiency of agrobacterium tumefaciens mediated transformation of aspergillus fumigatus by using pyrg as a recessive selectable marker. | 2008 | 18560466 |
| development of transgenic artemisia annua (chinese wormwood) plants with an enhanced content of artemisinin, an effective anti-malarial drug, by hairpin-rna-mediated gene silencing. | artemisinin is an effective anti-malarial drug isolated from artemisia annua l. (chinese wormwood), but the content of artemisinin in a. annua is low. in the present study we explored the possibility of using genetic engineering to increase the artemisinin content of a. annua by suppressing the expression of sqs (squalene synthase), a key enzyme of sterol pathway (a pathway competitive with that of artemisinin biosynthesis) by means of a hairpin-rna-mediated rnai (rna interference) technique. a ... | 2009 | 18564056 |
| crystal structure of a carbonyl reductase from candida parapsilosis with anti-prelog stereospecificity. | a novel short-chain (s)-1-phenyl-1,2-ethanediol dehydrogenase (scr) from candida parapsilosis exhibits coenzyme specificity for nadph over nadh. it catalyzes an anti-prelog type reaction to reduce 2-hydroxyacetophenone into (s)-1-phenyl-1,2-ethanediol. the coding gene was overexpressed in escherichia coli and the purified protein was crystallized. the crystal structure of the apo-form was solved to 2.7 a resolution. this protein forms a homo-tetramer with a broken 2-2-2 symmetry. the overall fol ... | 2008 | 18566346 |
| quorum sensing coordinates brute force and stealth modes of infection in the plant pathogen pectobacterium atrosepticum. | quorum sensing (qs) in vitro controls production of plant cell wall degrading enzymes (pcwdes) and other virulence factors in the soft rotting enterobacterial plant pathogen pectobacterium atrosepticum (pba). here, we demonstrate the genome-wide regulatory role of qs in vivo during the pba-potato interaction, using a pba-specific microarray. we show that 26% of the pba genome exhibited differential transcription in a qs (expi-) mutant, compared to the wild-type, suggesting that qs may make a gre ... | 2008 | 18566662 |
| identification of the gene encoding the alpha1,3-mannosyltransferase (alg3) in arabidopsis and characterization of downstream n-glycan processing. | glycosyltransferases are involved in the biosynthesis of lipid-linked n-glycans. here, we identify and characterize a mannosyltransferase gene from arabidopsis thaliana, which is the functional homolog of the alg3 (dol-p-man:man5glcnac2-pp-dol alpha1,3-mannosyl transferase) gene in yeast. the at alg3 protein can complement a deltaalg3 yeast mutant and is localized to the endoplasmic reticulum in yeast and in plants. a homozygous t-dna insertion mutant, alg3-2, was identified in arabidopsis with ... | 2008 | 18567790 |
| a distinct endosomal ca2+/mn2+ pump affects root growth through the secretory process. | ca(2+) is required for protein processing, sorting, and secretion in eukaryotic cells, although the particular roles of the transporters involved in the secretory system of plants are obscure. one endomembrane-type ca-atpase from arabidopsis (arabidopsis thaliana), ateca3, diverges from ateca1, ateca2, and ateca4 in protein sequence; yet, ateca3 appears similar in transport activity to the endoplasmic reticulum (er)-bound ateca1. expression of ateca3 in a yeast (saccharomyces cerevisiae) mutant ... | 2008 | 18567829 |
| expression of hiv-1 antigens in plants as potential subunit vaccines. | human immunodeficiency virus type 1 (hiv-1) has infected more than 40 million people worldwide, mainly in sub-saharan africa. the high prevalence of hiv-1 subtype c in southern africa necessitates the development of cheap, effective vaccines. one means of production is the use of plants, for which a number of different techniques have been successfully developed. hiv-1 pr55gag is a promising hiv-1 vaccine candidate: we compared the expression of this and a truncated gag (p17/p24) and the p24 cap ... | 2008 | 18573204 |
| skim milk enhances the preservation of thawed -80 degrees c bacterial stocks. | the results from bacterial strain recovery efforts following hurricanes katrina and rita are reported. over 90% of strains frozen in 10% skim milk were recovered whereas various recovery rates were observed for glycerol-stored stocks (56% and 94% of escherichia coli, depending upon the laboratory). these observations led to a viability comparison of streptococcus pyogenes, campylobacter jejuni, borrelia burgdorferi, salmonella enterica subsp. typhimurium, pseudomonas aeruginosa and e. coli strai ... | 2008 | 18573555 |
| evidence of recent interkingdom horizontal gene transfer between bacteria and candida parapsilosis. | to date very few incidences of interdomain gene transfer into fungi have been identified. here, we used the emerging genome sequences of candida albicans wo-1, candida tropicalis, candida parapsilosis, clavispora lusitaniae, pichia guilliermondii, and lodderomyces elongisporus to identify recent interdomain hgt events. we refer to these as ctg species because they translate the ctg codon as serine rather than leucine, and share a recent common ancestor. | 2008 | 18577206 |
| spermidine exodus and oxidation in the apoplast induced by abiotic stress is responsible for h2o2 signatures that direct tolerance responses in tobacco. | polyamines (pas) exert a protective effect against stress challenges, but their molecular role in this remains speculative. in order to detect the signaling role of apoplastic pa-derived hydrogen peroxide (h2o2) under abiotic stress, we developed a series of tobacco (nicotiana tabacum cv xanthi) transgenic plants overexpressing or downregulating apoplastic polyamine oxidase (pao; s-pao and a-pao plants, respectively) or downregulating s-adenosyl-l-methionine decarboxylase (samdc plants). upon sa ... | 2008 | 18577660 |
| expression of chlamydophila psittaci momp heat-labile toxin b subunit fusion gene in transgenic rice. | a dna fragment encoding the momp gene of chlamydophila psittaci was fused to the heat-labile toxin b subunit gene (ltb-momp) and transferred into rice callus by agrobacterium tumefaciens-mediated transformation. the ltb-momp fusion gene was detected in genomic dna from transformed rice leaves by southern blot and rt-pcr amplification. synthesis and assembly of the ltb-momp fusion protein into pentamers was detected in transformed leaf extracts by immunoblot analysis. binding of the pentamers to ... | 2008 | 18579410 |
| the linear chromosome of the plant-pathogenic mycoplasma 'candidatus phytoplasma mali'. | phytoplasmas are insect-transmitted, uncultivable bacterial plant pathogens that cause diseases in hundreds of economically important plants. they represent a monophyletic group within the class mollicutes (trivial name mycoplasmas) and are characterized by a small genome with a low gc content, and the lack of a firm cell wall. all mycoplasmas, including strains of 'candidatus (ca.) phytoplasma asteris' and 'ca. p. australiense', examined so far have circular chromosomes, as is the case for almo ... | 2008 | 18582369 |
| bridging the gap between plant and mammalian polyamine catabolism: a novel peroxisomal polyamine oxidase responsible for a full back-conversion pathway in arabidopsis. | in contrast to animals, where polyamine (pa) catabolism efficiently converts spermine (spm) to putrescine (put), plants have been considered to possess a pa catabolic pathway producing 1,3-diaminopropane, delta(1)-pyrroline, the corresponding aldehyde, and hydrogen peroxide but unable to back-convert spm to put. arabidopsis (arabidopsis thaliana) genome contains at least five putative pa oxidase (pao) members with yet-unknown localization and physiological role(s). atpao1 was recently identified ... | 2008 | 18583528 |
| the molecular structure of epoxide hydrolase b from mycobacterium tuberculosis and its complex with a urea-based inhibitor. | mycobacterium tuberculosis (mtb), the intracellular pathogen that infects macrophages primarily, is the causative agent of the infectious disease tuberculosis in humans. the mtb genome encodes at least six epoxide hydrolases (ehs a to f). ehs convert epoxides to trans-dihydrodiols and have roles in drug metabolism as well as in the processing of signaling molecules. herein, we report the crystal structures of unbound mtb ehb and mtb ehb bound to a potent, low-nanomolar (ic(50) approximately 19 n ... | 2008 | 18585390 |
| structural basis of the transcriptional regulation of the proline utilization regulon by multifunctional puta. | the multifunctional escherichia coli proline utilization a (puta) flavoprotein functions both as a membrane-associated proline catabolic enzyme and as a transcriptional repressor of the proline utilization genes puta and putp. to better understand the mechanism of transcriptional regulation by puta, we have mapped the put-regulatory region, determined a crystal structure of the puta ribbon-helix-helix domain (puta52, a polypeptide corresponding to residues 1-52 of e. coli puta) complexed with dn ... | 2008 | 18586269 |
| conversion of bacillus subtilis ohrr from a 1-cys to a 2-cys peroxide sensor. | ohrr proteins can be divided into two groups based on their inactivation mechanism: 1-cys (represented by bacillus subtilis ohrr) and 2-cys (represented by xanthomonas campestris ohrr). a conserved cysteine residue near the amino terminus is present in both groups of proteins and is initially oxidized to the sulfenic acid. the b. subtilis 1-cys ohrr protein is subsequently inactivated by formation of a mixed-disulfide bond with low-molecular-weight thiols or by cysteine overoxidation to sulfinic ... | 2008 | 18586944 |
| metabolic engineering of aliphatic glucosinolates in chinese cabbage plants expressing arabidopsis mam1, cyp79f1, and cyp83a1. | three arabidopsis cdnas, mam1, cyp79f1, and cyp83a1, required for aliphatic glucosinolate biosynthesis were introduced into chinese cabbage by agrobacterium tumefaciens-mediated transformation. the transgenic lines overexpressing mam1 or cyp83a1 showed wild-type phenotypes. however, all the lines overexpressing cyp79f1 displayed phenotypes different from wild type with respect to the stem thickness as well as leaf width and shape. glucosinolate contents of the transgenic plants were compared wit ... | 2008 | 18593532 |
| structure and mechanism of gumk, a membrane-associated glucuronosyltransferase. | xanthomonas campestris gumk (beta-1,2-glucuronosyltransferase) is a 44-kda membrane-associated protein that is involved in the biosynthesis of xanthan, an exopolysaccharide crucial for this bacterium's phytopathogenicity. xanthan also has many important industrial applications. the gumk enzyme is the founding member of the glycosyltransferase family 70 of carbohydrate-active enzymes, which is composed of bacterial glycosyltransferases involved in exopolysaccharide synthesis. no x-ray structures ... | 2008 | 18596046 |
| a common genomic framework for a diverse assembly of plasmids in the symbiotic nitrogen fixing bacteria. | this work centres on the genomic comparisons of two closely-related nitrogen-fixing symbiotic bacteria, rhizobium leguminosarum biovar viciae 3841 and rhizobium etli cfn42. these strains maintain a stable genomic core that is also common to other rhizobia species plus a very variable and significant accessory component. the chromosomes are highly syntenic, whereas plasmids are related by fewer syntenic blocks and have mosaic structures. the pairs of plasmids p42f-prl12, p42e-prl11 and p42b-prl9 ... | 2008 | 18596979 |
| an in vivo gene deletion system for determining temporal requirement of bacterial virulence factors. | analysis of phenotypes associated with specific mutants has been instrumental in determining the roles of a bacterial gene in a biological process. however, this technique does not allow one to address whether a specific gene or gene set is necessary to maintain such a process once it has been established. in the study of microbial pathogenesis, it is important but difficult to determine the temporal requirement of essential pathogenic determinants in the entire infection cycle. here we report a ... | 2008 | 18599442 |
| tomato protein kinase 1b mediates signaling of plant responses to necrotrophic fungi and insect herbivory. | the tomato protein kinase 1 (tpk1b) gene encodes a receptor-like cytoplasmic kinase localized to the plasma membrane. pathogen infection, mechanical wounding, and oxidative stress induce expression of tpk1b, and reducing tpk1b gene expression through rna interference (rnai) increases tomato susceptibility to the necrotrophic fungus botrytis cinerea and to feeding by larvae of tobacco hornworm (manduca sexta) but not to the bacterial pathogen pseudomonas syringae. tpk1b rnai seedlings are also im ... | 2008 | 18599583 |
| viroid-induced symptoms in nicotiana benthamiana plants are dependent on rdr6 activity. | viroids are small self-replicating rnas that infect plants. how these noncoding pathogenic rnas interact with hosts to induce disease symptoms is a long-standing unanswered question. recent experimental data have led to the suggestive proposal of a pathogenic model based on the rna silencing mechanism. however, evidence of a direct relation between key components of the rna silencing pathway and symptom expression in infected plants remains elusive. to address this issue, we used a symptomatic t ... | 2008 | 18599649 |
| a role for a menthone reductase in resistance against microbial pathogens in plants. | plants elaborate a vast array of enzymes that synthesize defensive secondary metabolites in response to pathogen attack. here, we isolated the pathogen-responsive camnr1 [menthone: (+)-(3s)-neomenthol reductase] gene, a member of the short-chain dehydrogenase/reductase (sdr) superfamily, from pepper (capsicum annuum) plants. gas chromatography-mass spectrometry analysis revealed that purified camnr1 and its ortholog atsdr1 from arabidopsis (arabidopsis thaliana) catalyze a menthone reduction wit ... | 2008 | 18599651 |
| structural basis for rna-silencing suppression by tomato aspermy virus protein 2b. | the 2b proteins encoded by cucumovirus act as post-transcriptional gene silencing suppressors to counter host defence during infection. here we report the crystal structure of tomato aspermy virus 2b (tav2b) protein bound to a 19 bp small interfering rna (sirna) duplex. tav2b adopts an all alpha-helix structure and forms a homodimer to measure sirna duplex in a length-preference mode. tav2b has a pair of hook-like structures to recognize simultaneously two alpha-helical turns of a-form rna duple ... | 2008 | 18600235 |
| modeling growth and succinoglucan production by agrobacterium radiobacter ncib 9042 in batch cultures. | wild-type agrobacterium radiobacter ncib 9042 has been cultivated in batch cultures on a synthetic medium which was adapted for growth and succinoglucan production. experiments were carried out in a 4-l stirred-tank aerated reactor. glucose, biomass, polysaccharide, protein, and inorganic- and organic-nitrogen concentrations were measured, and oxygen consumption and co(2) production rates were obtained by a gas-balance technique. nitrogen balance shows that inorganic nitrogen is entirely recover ... | 1991 | 18600699 |
| enhanced soybean infection by the legume "super-virulent" agrobacterium tumefaciens strain kat23. | agrobacterium tumefaciens kat23 harbors a nopaline-type ti plasmid and is "super-virulent" to soybean (glycine max) and other leguminous plants. the right and left border sequences of the essential cis-element for t-dna transfer were removed in order to utilize the high infectivity of this strain in an agrobacterium-mediated soybean transformation system. the resulting strain, named soy2, showed no oncogenic activity. after inoculation with disarmed soy2 harboring binary vector pig121-hm and pca ... | 2008 | 18603788 |
| broad-host-range expression vectors with tightly regulated promoters and their use to examine the influence of trar and tram expression on ti plasmid quorum sensing. | experiments requiring strong repression and precise control of cloned genes can be difficult to conduct because of the relatively high basal level of expression of currently employed promoters. we report the construction of a family of vectors that contain a reengineered laci(q)-lac promoter-operator complex in which cloned genes are strongly repressed in the absence of inducer. the vectors, all based on the broad-host-range plasmid pbbr1, are mobilizable and stably replicate at moderate copy nu ... | 2008 | 18606801 |
| vv-amp1, a ripening induced peptide from vitis vinifera shows strong antifungal activity. | latest research shows that small antimicrobial peptides play a role in the innate defense system of plants. these peptides typically contribute to preformed defense by developing protective barriers around germinating seeds or between different tissue layers within plant organs. the encoding genes could also be upregulated by abiotic and biotic stimuli during active defense processes. the peptides display a broad spectrum of antimicrobial activities. their potent anti-pathogenic characteristics ... | 2008 | 18611251 |
| cytosolic and plastoglobule-targeted carotenoid dioxygenases from crocus sativus are both involved in beta-ionone release. | saffron, the processed stigma of crocus sativus, is characterized by the presence of several apocarotenoids that contribute to the color, flavor, and aroma of the spice. however, little is known about the synthesis of aroma compounds during the development of the c. sativus stigma. the developing stigma is nearly odorless, but before and at anthesis, the aromatic compound beta-ionone becomes the principal norisoprenoid volatile in the stigma. in this study, four carotenoid cleavage dioxygenase ( ... | 2008 | 18611853 |
| dolichol biosynthesis and its effects on the unfolded protein response and abiotic stress resistance in arabidopsis. | dolichols are long-chain unsaturated polyisoprenoids with multiple cellular functions, such as serving as lipid carriers of sugars used for protein glycosylation, which affects protein trafficking in the endoplasmic reticulum. the biological functions of dolichols in plants are largely unknown. we isolated an arabidopsis thaliana mutant, lew1 (for leaf wilting1), that showed a leaf-wilting phenotype under normal growth conditions. lew1 encoded a cis-prenyltransferase, which when expressed in esc ... | 2008 | 18612099 |
| improvement of shikonin productivity in lithospermum erythrorhizon cell culture by alternating carbon and nitrogen feeding strategy. | stationary phase cell suspension cultures of agrobacterium tumefaciens transformed lithospermum erythrorhizon respond to additions of sucrose-rich (c-rich) medium with a 2-3-fold increase in the accumulation of shikonin derivatives and a 3-3.5-fold increase in the accumulation of soluble phenolics while showing a modest (10-30%) increase in cell concentration. conversely, the addition of nitrate-rich (n-rich) medium resulted in 25-35% increase in biomass concentration but only 2-9% increase in s ... | 1993 | 18613125 |
| expression of dm-amp1 in rice confers resistance to magnaporthe oryzae and rhizoctonia solani. | magnaporthe oryzae and rhizoctonia solani, are among the most important pathogens of rice, severely limiting its productivity. dm-amp1, an antifungal plant defensin from dahlia merckii, was expressed in rice (oryza sativa l. sp. indica cv. pusa basmati 1) using agrobacterium tumefaciens-mediated transformation. expression levels of dm-amp1 ranged from 0.43% to 0.57% of total soluble protein in transgenic plants. it was observed that constitutive expression of dm-amp1 suppresses the growth of m. ... | 2009 | 18618285 |
| a transformation procedure for recalcitrant tomato by addressing transgenic plant-recovery limiting factors. | agrobacterium tumefaciens technology is the battle horse for tomato genetic transformation. however, tomato varieties with low regeneration capacity are very difficult to transform. in the past, tomato transformation through agrobacterium infection was focused on varieties capable of high regeneration yield, while successful transformation of low regenerable cultivars has not been reported. the genotype response to tissue culture conditions is believed to drive the frequency of regeneration of t ... | 2008 | 18618483 |
| the yeast saccharomyces cerevisiae: a versatile model system for the identification and characterization of bacterial virulence proteins. | microbial pathogens utilize complex secretion systems to deliver proteins into host cells. these effector proteins target and usurp host cell processes to promote infection and cause disease. while secretion systems are conserved, each pathogen delivers its own unique set of effectors. the identification and characterization of these effector proteins has been difficult, often limited by the lack of detectable signal sequences and functional redundancy. model systems including yeast, worms, flie ... | 2008 | 18621006 |
| excess seqa leads to replication arrest and a cell division defect in vibrio cholerae. | although most bacteria contain a single circular chromosome, some have complex genomes, and all vibrio species studied so far contain both a large and a small chromosome. in recent years, the divided genome of vibrio cholerae has proven to be an interesting model system with both parallels to and novel features compared with the genome of escherichia coli. while factors influencing the replication and segregation of both chromosomes have begun to be elucidated, much remains to be learned about t ... | 2008 | 18621898 |
| artificial septal targeting of bacillus subtilis cell division proteins in escherichia coli: an interspecies approach to the study of protein-protein interactions in multiprotein complexes. | bacterial cell division is mediated by a set of proteins that assemble to form a large multiprotein complex called the divisome. recent studies in bacillus subtilis and escherichia coli indicate that cell division proteins are involved in multiple cooperative binding interactions, thus presenting a technical challenge to the analysis of these interactions. we report here the use of an e. coli artificial septal targeting system for examining the interactions between the b. subtilis cell division ... | 2008 | 18621900 |
| indian mustard aquaporin improves drought and heavy-metal resistance in tobacco. | an aquaporin cdna bjpip1 isolated from heavy-metal accumulator indian mustard (brassica juncea l.) encodes a 286-residue protein. the deduced amino acid sequence of bjpip1 with six putative transmembrane domains showed highest identity (85-99%) to pip1 subfamily members. semi-quantitative rt-pcr analysis revealed that bjpip1 transcripts were more abundantly expressed in roots compared to aerial parts of indian mustard. however, the expression of bjpip1 in leaves was up-regulated by drought, salt ... | 2008 | 18622723 |
| kinetic model of disaccharide oxidation by agrobacterium tumefaciens. | disaccharides were microbially transformed to their corresponding 3-keto-derivatives by resting cells of agrobacterium tumefaciens ncppb 396. the kinetics and yield of this highly specific oxidation depend on several factors. the oxygen concentration especially has a major influence on the production of 3-keto-derivatives and was investigated kinetically with respect to low stationary oxygen concentrations in solution. experiments showed unconventional results that conflicted with normal michael ... | 1995 | 18623455 |