Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| involvement of azospirillum brasilense plasmid dna in the production of indole acetic acid. | indole acetic acid (iaa) production in azospirillum brasilense strain sp245 is controlled by a 85 mda plasmid naturally present in this bacterium. in the presence of l-tryptophan, anthranilic acid production and almost no iaa production occurs in a derivative strain harbouring a tn5-mob insertion in the 85 mda plasmid. agrobacterium tumefaciens strain gm19023, upon transfer of tn5-mob labelled 85 mda plasmid of a. brasilense sp245, gains the ability to produce anthranilic acid. | 1990 | 2283026 |
| identification and quantitation of corrinoid precursors of cobalamin from pseudomonas denitrificans by high-performance liquid chromatography. | after initial pretreatment for removal of interfering substances, corrinoid precursors of cobalamin from cultures of pseudomonas denitrificans were separated by hplc with a gradient elution system. in this system, all the following compounds are separated in their dicyano form, and retention times are given: cobyrinic acid; cobyrinic acid a-amide; cobyrinic acid c-amide; cobyrinic acid g-amide; cobyrinic acid a,g-diamide; cobyrinic acid c,g-diamide; cobyrinic acid a,c-diamide; cobyrinic acid a,c ... | 1990 | 2278386 |
| agrobacterium plasmids encode structurally and functionally different loci for catabolism of agrocinopine-type opines. | agrobacterium tumefaciens strains c58, t37, k827 and j73, a. rhizogenes strains a4 and 15834, and a. radiobacter strain k299 were all susceptible to agrocin 84 and this sensitivity was enhanced in each case by addition of agrocinopines a and b. analysis of transconjugants showed that sensitivity of strain a4 to agrocin 84 was encoded by para4a and not by the rhizogenic plasmid, pria4. the acc region of the a. tumefaciens nopaline-type ti plasmid ptic58, contained on the recombinant plasmid pthh2 ... | 1990 | 2270086 |
| vird2 gene product from the nopaline plasmid ptic58 has at least two activities required for virulence. | virulence genes vird1 and vird2 are required for t-dna processing in agrobacterium tumefaciens. the regions within vird2 contributing to t-dna processing and virulence were investigated. some insertional mutations in vird2 prevented t-dna border endonucleolytic cleavage and produced an avirulent phenotype. however, a non-polar insertion immediately after bp 684 of the 1344 bp open reading frame of vird2 did not inhibit endonucleolytic cleavage but still caused a loss of virulence. this suggested ... | 1990 | 2263456 |
| characterization of the virg binding site of agrobacterium tumefaciens. | expression of agrobacterium tumefaciens virulence (vir) genes is dependent on the presence of a conserved 'vir box' sequence in their 5' nontranscribed regions. the location and number of these sequences vary considerably in different vir genes. site-directed mutagenesis was used to identify the functional vir box(es) of virb, virc and vird. for virb expression both vir box b1 and b2 are required but only the vir box b1 is absolutely essential. of the five vir boxes of virc and vird two are requ ... | 1990 | 2263453 |
| agrobacterium tumefaciens t-dna gene 6b stimulates rol-induced root formation, permits growth at high auxin concentrations and increases root size. | all agrobacterium tumefaciens strains studied up to now transfer an active 6b gene to plant cells. however, the role of this gene in natural tumour induction is unknown. various effects of 6b on plant cell growth have been described, but the precise mechanism by which 6b causes these effects has not been elucidated. earlier experiments indicated that the 6b gene might increase auxin sensitivity as do the a. rhizogenes rol genes. the 6b gene from tm4 (t-6b) was therefore compared with the rolb an ... | 1990 | 2259331 |
| osmoregulation in agrobacterium tumefaciens: accumulation of a novel disaccharide is controlled by osmotic strength and glycine betaine. | we have investigated the mechanism of osmotic stress adaptation (osmoregulation) in agrobacterium tumefaciens biotype i (salt-tolerant) and biotype ii (salt-sensitive) strains. using natural-abundance 13c nuclear magnetic resonance spectroscopy, we identified all organic solutes that accumulated to significant levels in osmotically stressed cultures. when stressed, biotype i strains (c58, nt1, and a348) accumulated glutamate and a novel disaccharide, beta-fructofuranosyl-alpha-mannopyranoside, c ... | 1990 | 2254260 |
| purification, cloning, and primary structure of an enantiomer-selective amidase from brevibacterium sp. strain r312: structural evidence for genetic coupling with nitrile hydratase. | an enantiomer-selective amidase active on several 2-aryl and 2-aryloxy propionamides was identified and purified from brevibacterium sp. strain r312. oligonucleotide probes were designed from limited peptide sequence information and were used to clone the corresponding gene, named amda. highly significant homologies were found at the amino acid level between the deduced sequence of the enantiomer-selective amidase and the sequences of known amidases such as indoleacetamide hydrolases from pseudo ... | 1990 | 2254253 |
| enhancer sequences from arabidopsis thaliana obtained by library transformation of nicotiana tabacum. | in this paper we report on the use of a bidirectional enhancer cloning vehicle to isolate and characterize new enhancer sequences from arabidopsis thaliana. a library of a. thaliana genomic sau3a segments was constructed in escherichia coli in the binary plasmid enhancer cloning vehicle proa97. the t-dna based vector carries abbreviated tata regions from the cauliflower mosaic virus 35s transcription unit upstream of two genes. the library was transferred via triparental mating into agrobacteriu ... | 1990 | 2250645 |
| [new shuttle-type vectors for cloning in escherichia coli and agrobacterium tumefaciens]. | the vectors capable of replication in escherichia coli and agrobacterium tumefaciens have been constructed on the basis of the plasmid pub5502. the constructed vectors pva12, pva12-2, pva12-4 contain the mini-replicon and trimethoprim resistance gene (tp) of a broad host-range plasmid r388 (incw). the pva12 vector (8.8 kb) has been constructed by insertion of a kanamycin resistance gene (km) from the plasmid puc-4k into a psti site. it possesses 7 unique restriction sites for xhoi, smai, pvui, p ... | 1990 | 2233784 |
| characterization of the virb operon of an agrobacterium tumefaciens ti plasmid: nucleotide sequence and protein analysis. | the virulence regulon of the agrobacterium tumefaciens tic58 plasmid is composed of six operons, vira, virb, virg, virc, vird and vire, which direct the transfer of t-dna into plant cells. the 9.5 kbp virb operon is the largest of these operons and its entire nucleotide sequence was determined and found to contain eleven open reading frames (orfs). gene fusions of each virb orf to t7 phi 10 were made and overexpressed in escherichia coli to confirm that they encode proteins of predicted size. hy ... | 1990 | 2233252 |
| agrobacterium rhizogenes mutants that fail to bind to plant cells. | transposon insertion mutants of agrobacterium rhizogenes were screened to obtain mutant bacteria that failed to bind to carrot suspension culture cells. a light microscope binding assay was used. the bacterial isolates that were reduced in binding to carrot cells were all avirulent on bryophyllum diagremontiana leaves and on carrot root disks. the mutants did not appear to be altered in cellulose production. the composition of the medium affected the ability of the parent and mutant bacteria to ... | 1990 | 2228955 |
| [uvrd-like sequences in the genome of agrobacterium tumefaciens]. | 1990 | 2227394 | |
| isolation of the replication dna region from a rhizobium plasmid and examination of its potential as a replicon for rhizobiaceae cloning vectors. | the dna region essential for replication and stability of a native plasmid (ptm5) from rhizobium sp. (hedysarum) has been identified and isolated within a 5.4-kb psti restriction fragment. the isolation of this region was accomplished by cloning endonuclease-restricted ptm5 dna into a cole1-type replicon and selecting the recombinant plasmids containing the ptm5 replicator (ptm5 derivative plasmids) by their ability to replicate in rhizobium. dna homology studies revealed that ptm5-like replicon ... | 1990 | 2217572 |
| physical map and properties of a 90-mda plasmid of azospirillum brasilense sp7. | homology was previously detected between the dna restriction fragments containing rhizobium meliloti nodulation genes and the 90-mda plasmid, p90, of azospirillum brasilense sp7. two dna loci from sp7 genome that complement mutations in the exopolysaccharide synthesis genes, exob and exoc, of r. meliloti were also shown to be present on the plasmid. a more detailed characterization of the plasmid was undertaken to establish its physical map and to localize the nod homologies and other specific r ... | 1990 | 2217570 |
| transgenic nicotiana debneyii expressing viral coat protein are resistant to potato virus s infection. | the coat protein gene from potato virus s (pvs) was introduced into nicotiana debneyii by leaf disc transformation using agrobacterium tumefaciens. transgenic plants expressing the viral coat protein were highly resistant to subsequent infection by the me strain of pvs as indicated by an absence of symptom development and a lack of accumulation of virus in both the inoculated and upper leaves. as in reported experiments with plants expressing potato virus x coat protein, plants expressing pvs co ... | 1990 | 2212996 |
| mutational analysis of the virg protein, a transcriptional activator of agrobacterium tumefaciens virulence genes. | the virg protein of agrobacterium tumefaciens is required in conjunction with the vira protein for transcriptional activation of the virulence (vir) genes in response to plant phenolic compounds. these proteins are members of a family of two component regulatory systems. vir genes are activated via a cascade of phosphorylation reactions involving a specific aspartic acid residue of the virg protein. we have conducted a mutational analysis of the virg protein. by mutating conserved and nonconserv ... | 1990 | 2211523 |
| genetic and sequence analysis of an 8.7-kilobase pseudomonas denitrificans fragment carrying eight genes involved in transformation of precorrin-2 to cobyrinic acid. | a 8.7-kilobase dna fragment carrying pseudomonas denitrificans cob genes has been sequenced. the nucleotide sequence and the genetic analysis revealed that this fragment carries eight different cob genes (cobf to cobm). six of these genes have the characteristics of translationally coupled genes. cobi has been identified as s-adenosyl-l-methionine (sam):precorrin-2 methyltransferase structural gene because the encoded protein has the same nh2 terminus and molecular weight as those of the purifie ... | 1990 | 2211521 |
| inhibition by agrobacterium tumefaciens and pseudomonas savastanoi of development of the hypersensitive response elicited by pseudomonas syringae pv. phaseolicola. | injection into tobacco leaves of biotype 1 agrobacterium tumefaciens or of pseudomonas savastanoi inhibited the development of a visible hypersensitive response to the subsequent injection at the same site of pseudomonas syringae pv. phaseolicola. this interference with the hypersensitive response was not seen with injection of bacterial growth medium or escherichia coli cells. live a. tumefaciens cells were required for the inhibitory effect. various mutants and strains of a. tumefaciens were e ... | 1990 | 2211508 |
| extrachromosomal homologous recombination and gene targeting in plant cells after agrobacterium mediated transformation. | we determined whether t-dna molecules introduced into plant cells using agrobacterium are suitable substrates for homologous recombination. for the detection of such recombination events different mutant versions of a nptii construct were used. in a first set of experiments protoplasts of nicotiana tabacum sr1 were cocultivated with two agrobacterium tumefaciens strains. each strain contained a different t-dna, one carrying a 5' deleted nptii gene and the other a nptii gene with a 3' deletion. a ... | 1990 | 2209538 |
| complementation analysis of agrobacterium tumefaciens ti plasmid virb genes by use of a vir promoter expression vector: virb9, virb10, and virb11 are essential virulence genes. | the virb gene products of the agrobacterium tumefaciens tumor-inducing (ti) plasmid have been proposed to mediate t-dna transport through the bacterial cell wall into plant cells. previous genetic analysis of the approximately 9.5-kilobase-pair virb operon has been limited to transposon insertion mutagenesis. due to the polarity of the transposon insertions, only the last gene in the operon, virb11, is known to provide an essential virulence function. we have now begun to assess the contribution ... | 1990 | 2203743 |
| in vitro activity of ljc10,627, a new carbapenem antibiotic with high stability to dehydropeptidase i. | the in vitro activity of ljc10,627, a new carbapenem, was compared with those of imipenem and ceftazidime. ljc10,627 had broad-spectrum activity against gram-positive and gram-negative clinical isolates. the mics of this compound for 90% of members of the family enterobacteriaceae tested (mic90s), including strains resistant to ceftazidime, ranged from 0.1 to 25 micrograms/ml. ljc10,627 inhibited pseudomonas aeruginosa at an mic90 of 3.13 micrograms/ml; it thus was twofold more active than imipe ... | 1990 | 2203313 |
| molecular characterization of the vir regulon of agrobacterium tumefaciens: complete nucleotide sequence and gene organization of the 28.63-kbp regulon cloned as a single unit. | the entire vir regulon of agrobacterium tumefaciens was subcloned and the complete 28.6-kbp nucleotide sequence was determined. the regulon was cloned as a single unit into two replicons, one of which replicates at a high copy number in this bacterium, and a second which has broad-host-range features to replicate in other gram-negative bacteria. these vir region plasmids are able to confer in trans the processing and transfer activities on a second plasmid containing the t-dna. in the high copy ... | 1990 | 2194232 |
| characteristics of the nopaline catabolic plasmid in agrobacterium strains k84 and k1026 used for biological control of crown gall disease. | wild-type agrobacterium radiobacter strain 84 and its tra- derivative k1026, used for biological control of crown gall disease, each contain the plasmid patk84b. it confers incompatibility to tumor-inducing (ti) plasmids of pathogenic a. tumefaciens, thus preventing transfer of ti plasmids into k84 and k1026, and the consequent development of pathogens resistant to the specific antibiotic, agrocin 84 produced by k84 and k1026. patk84b also resembles one group of ti plasmids in its capacity for d ... | 1990 | 2194227 |
| transcriptional induction of an agrobacterium regulatory gene at tandem promoters by plant-released phenolic compounds, phosphate starvation, and acidic growth media. | transcription of the virg gene of agrobacterium tumefaciens was previously shown to be expressed from two tandem promoters and to be responsive to three stimuli: plant-released phenolic compounds, phosphate starvation, and acidic media. in this report, i describe a set of deletions and other alterations of the 5' end of virg that show that the upstream promoter (p1) is necessary for induction by phenolic compounds and by phosphate starvation, whereas the downstream promoter (p2) is induced by ac ... | 1990 | 2185220 |
| plant chromosome/marker gene fusion assay for study of normal and truncated t-dna integration events. | during agrobacterium tumefaciens infection, the t-dna flanked by 24 bp imperfect direct repeats is transferred and stably integrated into the plant chromosome at random positions. here we measured the frequency with which a promoterless reporter gene is activated after insertion into the nicotiana tabacum sr1 genome. when adjacent to the right or left t-dna border sequences, at least 35% of the transformants express the marker gene, suggesting preferential t-dna insertion (greater than 70%) in t ... | 1990 | 2177527 |
| excision of a ds-like maize transposable element (ac delta) in a transient assay in petunia is enhanced by a truncated coding region of the transposable element ac. | the excision of a ds-like transposable element (ac delta) is mediated in trans by the transposable element ac or its derivatives in petunia protoplasts cotransfected with two plasmid dnas. excision restores the activity of the beta-glucuronidase (gus) gene that is otherwise shut off by the presence of ac delta in its leader sequence. a transient expression assay (histochemical test) is used to detect the beta-glucuronidase activity at the protoplast to detect the beta-glucuronidase activity at t ... | 1990 | 2177522 |
| evidence that modulation requires sequences downstream of the promoters of two vir-repressed genes of bordetella pertussis. | gene expression in bordetella pertussis is altered by environmental signals in a process called antigenic modulation. in the presence of modulating signals, expression of several known virulence factors and outer membrane proteins is coordinately reduced. from a bank of tnphoa fusions, we have identified five genes whose expression profiles are reciprocal of those of the major virulence determinants; that is, alkaline phosphatase activity is maximal during growth in the presence of the modulator ... | 1990 | 2174866 |
| enterobactin-mediated iron transport in pseudomonas aeruginosa. | a pyoverdine-deficient strain of pseudomonas aeruginosa was unable to grow in an iron-deficient minimal medium in the presence of the nonmetabolizable iron chelator ethylene diamine-di(omega-hydroxyphenol acetic acid) (eddha), although addition of enterobactin to eddha-containing minimal media did restore growth of the pyoverdine-deficient p. aeruginosa. consistent with the apparent ability of enterobactin to provide iron to p. aeruginosa, enterobactin-dependent 55fe3+ uptake was observed in cel ... | 1990 | 2174865 |
| pica, a novel plant-inducible locus on the agrobacterium tumefaciens chromosome. | we used the transposon mu di1681 to identify genes on the agrobacterium tumefaciens chromosome that are inducible by extracts from carrot roots. one such locus (pica, for plant inducible chromosomal), harbored by a. tumefaciens at156, was inducible 10- to 50-fold by these extracts. mutation of pica had no detectable effect upon bacterial growth or virulence under laboratory assay conditions. however, a. tumefaciens cells harboring a mutated pica locus aggregated into long "ropes" when incubated ... | 1990 | 2170328 |
| efficient transformation of agrobacterium tumefaciens by electroporation. | high-voltage electroporation was used to transform agrobacterium tumefaciens strains a136 and a348, reaching the efficiency of 1-3 x 10(8) transformants/micrograms dna. transformation frequency was dependent on the electrical field strength and the pulse length. no significant reduction in transformation efficiency was observed when the transforming dna contained sites sensitive to endonuclease atuci of a. tumefaciens. | 1990 | 2165971 |
| overexpression of vird1 and vird2 genes in agrobacterium tumefaciens enhances t-complex formation and plant transformation. | the vird1 and vird2 proteins encoded by an inducible locus of the virulence (vir) region of the agrobacterium tumefaciens ti plasmid are required for site-specific nicking at t-dna border sites. we have determined the nucleotide sequence of a 3.6-kilobase-pair fragment carrying the vird locus from nopaline ti plasmid ptic58. in contrast to the previous report (hagiya et al., proc. natl. acad. sci. usa 82:2669-2673, 1985), we found that the first three open reading frames were capable of encoding ... | 1990 | 2165478 |
| a chromosomal agrobacterium tumefaciens gene required for effective plant signal transduction. | the vir gene products of agrobacterium tumefaciens carry out the transfer of t-dna to the plant genome. effective transcriptional induction of the vir genes by plant signal molecules is controlled by two vir gene products, vira and virg. in this study we have identified and cloned a chromosomal region which is also required for vir gene induction. transposon insertions within this region reduce induction significantly and strongly attenuate virulence, resulting in a restricted host range for inf ... | 1990 | 2156804 |
| vir genes influence conjugal transfer of the ti plasmid of agrobacterium tumefaciens. | mutation of the genes vira, virb, virc, and virg of the agrobacterium tumefaciens octopine-type ti plasmid ptir10 was found to cause a 100- to 10,000-fold decrease in the frequency of conjugal transfer of this plasmid between agrobacterium cells. this effect was not absolute, however, in that it occurred only during early times (18 to 24 h) of induction of the conjugal transfer apparatus by octopine. induction of these mutant agrobacterium strains by octopine for longer periods (48 to 72 h) resu ... | 1990 | 2155206 |
| homologous recombination in plant cells after agrobacterium-mediated transformation. | a single amino-acid change in the acetolactate synthase (als) protein of tobacco confers resistance to the herbicide chlorsulfuron. a deleted, nonfunctional fragment from the acetolactate synthase gene, carrying the mutant site specifying chlorsulfuron resistance plus a closely linked novel restriction site marker, was cloned into a binary vector. tobacco protoplasts transformed with agrobacterium tumefaciens carrying this vector yielded chlorsulfuron-resistant colonies. dna gel blot analysis of ... | 1990 | 2152167 |
| a family of atpases involved in active partitioning of diverse bacterial plasmids. | low copy-number bacterial plasmids f (the classical escherichia coli sex factor) and prophage p1 encode partitioning functions which may provide fundamental insights into the active processes which ensure that bacterial genomes are segregated to both daughter cells prior to cell division. these partitioning systems involve two proteins: para and parb. we report that incc from the broad host-range plasmid rk2 is a member of the family of para partitioning proteins and that these proteins (as well ... | 1990 | 2149583 |
| structure and function of the promoter of the carrot v-type h(+)-atpase catalytic subunit gene. | we investigated the 5'-upstream region of the gene encoding the catalytic subunit of the v-type h(+)-atpase in daucus carota. a genomic sublibrary was screened with a cdna probe, and a 4-kilobase genomic clone was obtained covering the first two exons and about 3 kilobases of the 5'-upstream sequence. the intron/exon boundaries matched established consensus sequences. within 240 base pairs (bp) upstream of the initiation codon three putative tata boxes were found. ribonuclease protection and pri ... | 1990 | 2139875 |
| synthesis and self-assembly of a functional monoclonal antibody in transgenic nicotiana tabacum. | immunoglobulin light and heavy chains are synthesized in mammalian cells as precursors containing a signal peptide. processing and assembling result in formation of active antibodies. chimeric genes have been made containing the coding sequence of the barley alpha-amylase signal peptide which has been fused to cdnas coding for either the mature light or the mature heavy chain of a monoclonal antibody. a plasmid was constructed linking both chimeric genes under the control of plant active promote ... | 1990 | 2129424 |
| iaa synthesis and root induction with iaa genes under heat shock promoter control. | we have devised a heat shock-inducible indole-3-acetic acid (iaa) synthesis system for plant cells, which is based on the iaa genes of the agrobacterium tumefaciens t-dna and the heat shock promoter hsp70 of drosophila melanogaster. two dna constructs were tested: one contains the iaam gene linked to the hsp70 promoter (hsp70-iaam) and encodes the production of indoleacetamide (iam), the other contains hsp70-iaam and the wild-type iaah gene which codes for the conversion of iam into iaa (hsp70-i ... | 1990 | 2129423 |
| a bacterial peptide acting as a plant nuclear targeting signal: the amino-terminal portion of agrobacterium vird2 protein directs a beta-galactosidase fusion protein into tobacco nuclei. | agrobacterium tumefaciens is a soil bacterium capable of transferring dna to the genome of higher plants. of the virulence region-encoded proteins of the tumor-inducing (ti) plasmid of a. tumefaciens, the vird1 and vird2 proteins are essential for t-dna transfer to plant cells. these two proteins have been shown to be directly responsible for the formation of t-strands. vird2 was also shown to be firmly attached to the 5' termini of t-strands; these facts have led to its postulation as a pilot p ... | 1990 | 2124696 |
| sugar-mediated induction of agrobacterium tumefaciens virulence genes: structural specificity and activities of monosaccharides. | the virulence genes of agrobacterium tumefaciens are induced by specific plant phenolic metabolites and sugars (g. a. cangelosi, r. g. ankenbauer, and e. w. nester, proc. natl. acad. sci. usa, in press). in this report, monosaccharides, derivatives, and analogs which induce the vir regulon have been identified and the structural requirements for monosaccharide-mediated induction have been determined. pyranose sugars with equatorial hydroxyls at c-1, c-2, and c-3 displayed strong vir gene-inducin ... | 1990 | 2121715 |
| sugars induce the agrobacterium virulence genes through a periplasmic binding protein and a transmembrane signal protein. | phenolic plant metabolites such as acetosyringone induce transcription of the virulence (vir) genes of agrobacterium tumefaciens through the transmembrane vira protein. we report here that certain sugars induce the vir genes synergistically with phenolic inducers by way of a distinct regulatory pathway that includes vira and a chromosomally encoded virulence protein, chve. sequence comparison showed that chve is a periplasmic galactose-binding protein corresponding to the gbp1 protein isolated f ... | 1990 | 2118656 |
| identification of an agrobacterium tumefaciens virulence gene inducer from the pinaceous gymnosperm pseudotsuga menziesii. | inducible t-strand mobilization from the ti plasmid of agrobacterium tumefaciens to the genome of a plant host is mediated by the activation of a cascade of bacterial virulence genes. it is initiated when the bacterium senses the presence of a low molecular weight inducer secreted by the plant. although many hydroxyphenylpropanoid and phenolic compounds can activate the virulence cascade, the only native inducers that have been identified to date are acetosyringone and hydroxyacetosyringone. a n ... | 1990 | 2110367 |
| stereospecific abstraction of epsilon-pro-r-hydrogen of l-lysine by l-lysine epsilon-dehydrogenase from agrobacterium tumefaciens. | the stereochemical aspects of the l-lysine epsilon-dehydrogenase reaction were examined with (6r)-l-[6-3h]lysine and (6s)-dl-[6-3h]lysine. when (6s)-dl-[6-3h]lysine was used as a substrate, the tritium was found in the product, delta 1-piperideine-6-carboxylate. in contrast, the radioactivity from (6r)-l-[6-3h]lysine was not retained in the product. thus, the pro-r hydrogen at the prochiral c-6 carbon of l-lysine is specifically abstracted by the enzyme: the enzyme behaves stereochemically as an ... | 1990 | 2110154 |
| [demonstration of 3 functional domains responsible for a kinase activity in vira, a transmembrane sensory protein encoded by the ti plasmid of agrobacterium tumefaciens]. | high-level expression of chimeric vira genes were obtained by replacing the first codons of vira with the first codons of trpe. the fusion proteins encoded by these constructs were partially purified and one of them exhibited autokinase activity. therefore, protein phosphorylation may be an important feature of vira function. this allowed us to define the existence of three functional domains inside vira. | 1990 | 2105145 |
| transformation and regeneration of the self-incompatible species nicotiana alata link & otto. | a transformation and regeneration system has been developed for nicotiana alata, a plant which is being intensively studied as a model of gametophytic self-incompatibility. plantlets can be regenerated efficiently from seedling hypocotyls. kanamycin-resistant, transformed plants have been obtained by cocultivation of regenerating hypocotyls with agrobacterium tumefaciens strain lba4404 containing a binary vector. the transformation frequency was low with less than 1% of tissue explants regenerat ... | 1990 | 2102859 |
| characteristics of a strong promoter from figwort mosaic virus: comparison with the analogous 35s promoter from cauliflower mosaic virus and the regulated mannopine synthase promoter. | a segment of dna from the genome of figwort mosaic virus (fmv) strain m3 possesses promoter activity when tested in electroporated protoplasts from, and transgenic plants of, nicotiana tabacum cv. xanthi nc. the 1.1 kb dna segment, designated the '34s' promoter, is derived from a position on the fmv genome comparable to the position on the cauliflower mosaic virus (camv) genome containing the 35s promoter. the 34s and 35s promoters show approximately 63% nucleotide homology in the tata, ccact, a ... | 1990 | 2102823 |
| octopine and nopaline strains of agrobacterium tumefaciens differ in virulence; molecular characterization of the virf locus. | octopine and nopaline strains of agrobacterium tumefaciens were found to differ in virulence on nicotiana glauca. this difference is due to the absence of a functional virf locus, which is necessary for efficient tumorigenesis on n. glauca, from the nopaline ti plasmids. genetic studies and dna sequence analysis of the virf locus revealed that virf embraces one open reading frame coding for a hydrophilic protein with a molecular mass of 22,437 da. transcription of virf is directed from left to r ... | 1990 | 2101693 |
| functional analysis of a complex oncogene arrangement in biotype iii agrobacterium tumefaciens strains. | the ubiquitous grapevine-associated octopine/cucumopine ti plasmids of biotype iii agrobacterium tumefaciens strains carry two t regions, ta and tb, with a complex oncogene arrangement. within the octopine/cucumopine group, two main strain types were identified: 'large ta' strains with a ta region resembling the tl region of the biotype i octopine strain ach5 and 'small ta' strains with a similar t region organization as the 'large ta' strains but with a large internal ta deletion. structural an ... | 1990 | 2101690 |
| t-dna presence and opine production in tumors of picea abies (l.) karst induced by agrobacterium tumefaciens a281. | the hypervirulent agrobacterium tumefaciens strain a281 formed frequent tumors (31%) on picea abies (norway spruce), an economically important tree species in swedish forests. three-month-old seedlings were inoculated and tumors were established that grew hormone-independently in culture. tumors contained agropine and mannopine/mannopinic acid as determined by acid ph paper electrophoresis. in addition, dna hybridization studies showed that the dna from these tumor lines contained sequences homo ... | 1990 | 2101685 |
| localized transient expression of gus in leaf discs following cocultivation with agrobacterium. | a chimaeric gene has been constructed that expresses beta-d-glucuronidase (gus) in transformed plant tissues, but not in bacterial cells. this gene has proved extremely useful for monitoring transformation during the period immediately following gene transfer from agrobacterium tumefaciens. gus expression was detectable 2 days after inoculation, peaked at 3-4 days and then declined; if selection was imposed expression increased again after 10-14 days. the extent of transient expression after 4 d ... | 1990 | 2101312 |
| expression of a rice glutelin promoter in transgenic tobacco. | a chimeric gene consisting of the 5' flanking sequences of a rice glutelin gene (gt3) linked to the chloramphenicol acetyltransferase (cat) coding segment was introduced into tobacco via agrobacterium tumefaciens-mediated transformation. cat enzyme activity could be detected in extracts from seeds as early as 8 days after flowering and obtained a maximum level at 16 days after flowering, the onset of overall protein accumulation. significant expression of cat activity in non-seed tissues occurre ... | 1990 | 2101310 |
| specific binding of virg to the vir box requires a c-terminal domain and exhibits a minimum concentration threshold. | the positive regulatory protein virg from the virulence region of the ti plasmid of agrobacterium tumefaciens was first demonstrated to possess dna-binding capabilities using chromatographically purified protein and in vitro assays (powell et al., 1989). this paper is an extension of that research and presents evidence on the in vivo dna-binding properties of virg using a transcription interference assay. virg protein bound specifically to a 'vir box' response element and repressed transcription ... | 1990 | 2089226 |
| agrobacterium radiobacter bacteremia in a child with human immunodeficiency virus infection. | 1991 | 2062633 | |
| viable but nonculturable bacteria in drinking water. | klebsiella pneumoniae, enterobacter aerogenes, agrobacterium tumefaciens, streptococcus faecalis, micrococcus flavus, bacillus subtilis, and pseudomonas strains l2 and 719 were tested for the ability to grow and maintain viability in drinking water. microcosms were employed in the study to monitor growth and survival by plate counts, acridine orange direct counts (aodc), and direct viable counts (dvc). plate counts dropped below the detection limit within 7 days for all strains except those of b ... | 1991 | 2039237 |
| cloning and nucleotide sequence of the hema gene of agrobacterium radiobacter. | the hema gene of agrobacterium radiobacter atcc4718 was identified by hybridization with a hema probe from rhizobium meliloti and cloned by complementation of a hema mutant of escherichia coli k12. e. coli hema transformants carrying the hema gene of agrobacterium showed delta-aminolevulinic acid synthetase (delta-alas) activity in vitro. the hema gene was carried on a 4.4 kb ecori fragment which could be reduced to a 2.6 kb ecori-ssti fragment without affecting its complementing or delta-alas a ... | 1991 | 2034217 |
| studies on heterologous expression of rhizobium meliloti nifa gene and oxygen sensitivity of its product. | when the r. meliloti (rm) nifa'-lacz fusion-carrying plasmids were introduced into the strains of agrobacterium tumefaciens, r. trifolii and r. astragalus, beta-galactosidase activity was demonstrated. however, activity was not induced by microaerobiosis. furthermore, r. meliloti nifa'-lacz fusion was also not expressed in the nodule bacteroids of r. trifolii and r. astragalus. we speculate that some factor(s) important for the induction of rm nifa presumed to be the fixlj regulatory system woul ... | 1991 | 2015065 |
| the virc and vird operons of the agrobacterium ti plasmid are regulated by the ros chromosomal gene: analysis of the cloned ros gene. | the ros chromosomal gene is present in octopine and nopaline strains of agrobacterium tumefaciens as well as in rhizobium meliloti. this gene encodes a 15.5-kda protein that specifically represses the virc and vird operons in the virulence region of the ti plasmid. the ros gene was cloned from a genomic bank by electroporation and complementation in agrobacterium cells. reporter fusion to the ros gene indicates that the level of transcription is controlled in part by autoregulation. a consensus ... | 1991 | 2013576 |
| nucleotide sequence analysis of a chloramphenicol-resistance determinant from agrobacterium tumefaciens and identification of its gene product. | the nucleotide sequence of a chloramphenicol-resistance (cmr) determinant from the gram- soil bacterium agrobacterium tumefaciens was determined, and its gene product was identified as cm acetyltransferase (cat). comparison of the amino acid sequences of the a. tumefaciens cat and various cat proteins of gram+ and gram- origin shows no homology between this and the other enzymes. | 1991 | 2013403 |
| a diffusible compound can enhance conjugal transfer of the ti plasmid in agrobacterium tumefaciens. | several octopine strains of agrobacterium tumefaciens were tested for ti plasmid (pti) transfer after induction by 400 micrograms of octopine per ml for 24 h. the strains could be divided into two groups, transfer efficient (trae) and transfer inefficient (traie); the respective rates of transfer were 0.77 x 10(-2) to 1.14 x 10(-2) and 0.33 x 10(-6) to 9.8 x 10(-6) plasmid transconjugant per donor cell. transfer efficiencies of traie strains were greatly increased when the time of induction was ... | 1991 | 2001991 |
| cloning and characterization of an amidase gene from rhodococcus species n-774 and its expression in escherichia coli. | for investigation of an unknown open reading frame which is present upstream of the nitrile hydratase (nhase) gene from rhodococcus sp. n-774, a longer dna fragment covering the entire gene was cloned in escherichia coli. nucleotide sequencing and detailed subcloning experiments predicted a single open reading frame consisting of 521 amino acid residues of mr 54,671. the amino acid sequence, especially its nh2-terminal portion, showed significant homology with those of indoleacetamide hydrolases ... | 1991 | 2001397 |
| sequence identity in the nick regions of incp plasmid transfer origins and t-dna borders of agrobacterium ti plasmids. | the incp antibiotic-resistance plasmids transfer to a broad range of bacterial species. the rk2 origin of dna transfer (orit) consists of a 250-base-pair segment including the single-stranded cleavage site (nic) needed to generate the dna strand believed to be transferred. deletion derivatives and a bank of hydroxylamine-generated orit mutants were screened for loss of transferability. dna regions flanking both sides of nic are required for optimal transfer of the orit clone. of the chemically i ... | 1991 | 1996345 |
| illegitimate recombination in plants: a model for t-dna integration. | agrobacterium tumefaciens is a soil bacterium capable of transferring dna (the t-dna) to the genome of higher plants, where it is then stably integrated. six t-dna inserts and their corresponding preinsertion sites were cloned from arabidopsis thaliana and analyzed. two t-dna integration events from nicotiana tabacum were included in the analysis. nucleotide sequence comparison of plant target sites before and after t-dna integration showed that the t-dna usually causes only a small (13-28 bp) d ... | 1991 | 1995418 |
| controlled expression of the transcriptional activator gene virg in agrobacterium tumefaciens by using the escherichia coli lac promoter. | the agrobacterium virg protein is normally expressed from two promoters in response to multiple stimuli, including plant-released phenolics (at promoter p1) and acidic growth media (at promoter p2). to simplify the analysis of vir gene induction, we sought to create agrobacterium strains in which virg could be expressed in a controllable fashion. to study the possibility of using the lac promoter and repressor, we constructed a plasmid containing the lac promoter fused to the lacz structural gen ... | 1991 | 1991713 |
| transport of nonmetabolizable opines by agrobacterium tumefaciens. | we have examined the uptake of [14c]octopine and [14c]nopaline by agrobacterium tumefaciens strains containing the c58 chromosomal background in medium suitable for the induction of vir genes. all strains tested could transport both of these opines, regardless of the presence or type of ti plasmid (octopine or nopaline) present in the bacterium. the transport of these opines required active cellular metabolism. nonradioactive octopine, nopaline, and arginine competed effectively with [14c]octopi ... | 1991 | 1987170 |
| a previously unrecognized glutamine synthetase expressed in klebsiella pneumoniae from the glnt locus of rhizobium leguminosarum. | using glnt dna of rhizobium meliloti as a hybridization probe we identified a r. leguminosarum biovar phaseoli (r. l. phaseoli) locus (glnt) expressing a glutamine synthetase activity in klebsiella pneumoniae. a 2.2 kb dna fragment from r. l. phaseoli was cloned to give plasmid pmw5a, which shows interspecific complementation of a k. pneumoniae glna mutant. the cloned sequence did not show cross-hybridization to glna or glnii, the genes coding for two glutamine synthetase isozymes of rhizobium s ... | 1990 | 1980142 |
| agrobacterium-mediated dna transfer in sugar pine. | dna transfer using agrobacterium tumefaciens has been demonstrated in sugar pine, pinus lambertiana dougl. shoots derived from cytokinin-treated cotyledons formed galls after inoculation with a. tumefaciens strains containing the plasmid ptibo542. a selectable marker, neomycin phosphotransferase ii, conferring resistance to kanamycin, was transferred into sugar pine using a binary armed vector system. callus proliferated from the galls grew without hormones and in some cases, kanamycin-resistant ... | 1990 | 1966486 |
| improved binary vectors for agrobacterium-mediated plant transformation. | improved plant transformation vectors were constructed which utilize the prihri origin of replication for highly stable maintenance in agrobacterium tumefaciens, the cole1 origin of replication for high copy maintenance in escherichia coli, and a gentamycin resistance gene as a strong selectable marker for bacteria. concise t-dna elements were engineered with border sequences from the tl-dna of ptia6, the tn5 neomycin phosphotransferase gene (npt ii) expressed from either camv 35s or mannopine s ... | 1990 | 1966276 |
| [design of an expression integrative vector and its application for introducing the human recombinant alfa interferon gene into plants]. | integrative expression vector pst6 was developed for dicote plant transformation. the vector contains neomycin phosphotransferase gene under control of pnos promoter which confers kanamycin resistance to transformed plant cells. the vector also includes expression cassette with strong constitutive 35s camv promoter for cloning of foreign genes. the human recombinant alfa interferon gene has been inserted into the expression cassette of pst6. recombinant plasmid obtained was transferred into agro ... | 1990 | 1964923 |
| nucleotide sequence analysis of is427 and its target sites in agrobacterium tumefaciens t37. | we have determined the nucleotide sequence of is427, an insertion sequence from agrobacterium tumefaciens t37, is427 is 1271 bp long, contains 16-bp imperfect terminal inverted repeats, and generates a 2-bp target sequence duplication. it is present at three sites in the ptit37 plasmid and is absent from the chromosome of a. tumefaciens t37. each of the is427 elements sequenced was near a site with sequence homology to integration host factor (ihf)-binding sites which suggested that ihf may be i ... | 1990 | 1963949 |
| repression of the camv 35s promoter by the octopine synthase enhancer element. | a 16 base-pair palindrome upstream of the agrobacterium tumefaciens octopine synthase (ocs) gene functions as a positive regulatory element in plant cells (ellis et al. (1987) embo j. 6, 3203-3208; fromm et al. (1989) plant cell 1, 977-984). we have converted it into a negative element by locating two copies flanking the tata-box of the constitutively expressed camv 35s promoter. the reduced promoter activity is very likely due to sterical hindrance of the ocs binding protein (ocstf) x ocs compl ... | 1991 | 1959656 |
| structural characterization of protein secretion genes of the bacterial phytopathogen xanthomonas campestris pathovar campestris: relatedness to secretion systems of other gram-negative bacteria. | the nucleotide sequence was determined of a 5.3 kb region of the xanthomonas campestris pathovar campestris genome carrying a gene cluster encoding protein secretion and pathogenicity functions. a putative promoter sequence and five open reading frames (orf) which may be part of an operon were revealed. the five predicted primary translation products comprise 531, 390, 147, 169 and 138 amino acids with mr values of 58,854, 42,299, 15,548, 18,214 and 15,108 respectively. a sixth, partial orf is a ... | 1991 | 1944223 |
| induction of the alka gene of escherichia coli in gram-negative bacteria. | a broad-host-range plasmid containing a fusion of the alka and lacz genes of escherichia coli was introduced into various aerobic and facultative gram-negative bacteria--33 species belonging to 19 genera--to study the induction of expression of the alka gene by alkylating agents. the bacteria included species of the families enterobacteriaceae, pseudomonadaceae, rhizobiaceae, vibrionaceae, neisseriaceae, rhodospirillaceae, and azotobacteraceae. results obtained show that all bacteria tested, exc ... | 1991 | 1938974 |
| a semiquantitative bioassay for relative virulence of agrobacterium tumefaciens strains on bryophyllum daigremontiana. | an assay to determine the relative virulence of wild-type and mutant strains of agrobacterium tumefaciens on leaves of bryophyllum daigremontiana has been developed. this assay is reproducible, is easy to learn, is not time consuming, and requires little space. the relative virulence of cellulose-minus mutants of a. tumefaciens was investigated with this assay. some of these mutants were unaltered in virulence, while others showed a marked reduction in virulence. | 1991 | 1938971 |
| role of t-region borders in agrobacterium host range. | the limited host range ab3 strain of agrobacterium tumefaciens induces tumors by transferring two t-regions, ta and tb. ta is a deleted version of the well-known biotype i octopine tl-region that lacks the iaa and ipt genes, but carries an intact oncogene, gene 6b, and typical left and right border sequences. tb carries two iaa genes that together code for the synthesis of indoleacetic acid. gene 6b and the iaa gene act synergistically when transferred in a coinoculation experiment. the ta-regio ... | 1991 | 1932812 |
| the nucleotide sequence and genome structure of the geminivirus miscanthus streak virus. | a tandem dimer of miscanthus streak virus (misv) dna was inserted into the t-dna of the binary plasmid vector pbin19 and agroinoculated into several monocotyledonous plants (monocots) using agrobacterium tumefaciens or a. rhizogenes. disease symptoms and geminate particles were produced in maize and panicum milaceum plants, and misv-specific double-stranded and single-stranded dnas were found in these plants. the nucleotide sequence of the infectious misv clone, consisting of 2672 nucleotides, w ... | 1991 | 1919519 |
| mismatch-specific dna breakdown in nuclear extract from tobacco (nicotiana tabacum) callus. | mismatch-specific enzymatic activity was sought for in nuclei from normal and transformed plant cells originating from tobacco (nicotiana tabacum) callus and crown gall tumor induced by agrobacterium tumefaciens. the specific enzymatic activity was assayed with substrates derived from synthetic oligonucleotides (19-mer sequences corresponding to the human k-ras gene). single-base changes in the middle of the sequence were the basis for creating heteroduplexes with all eight mismatches. homo- and ... | 1991 | 1912502 |
| regulation of agrobacterium tumefaciens t-cyt gene expression in leaves of transgenic potato (solanum tuberosum l. cv. désirée) is strongly influenced by plant culture conditions. | the promoter region of the agrobacterium tumefaciens t-cyt gene was linked in a translational fusion to the coding dna of the reporter gene uida (for beta-glucuronidase or gus protein; ec 3.2.1.31) and to nos 3' flanking dna. the chimaeric gene was introduced by agrobacterium transformation into potato (solanum tuberosum l. cv. désirée). in nine transgenic lines, the average gus levels were highest in extracts from stems and roots of in vitro grown plants (ca. 11,000 gus activity units per pmol ... | 1991 | 1912495 |
| expression of a brassica napus extensin gene in the vascular system of transgenic tobacco and rape plants. | the organs and tissues where the brassica napus exta extensin gene is expressed have been identified. the exta gene with 3.75 kb of 5' flanking sequence was transferred to tobacco via disarmed agrobacterium tumefaciens vectors and transgenic plants regenerated. the gene was found to be inactive in transgenic tobacco leaf, but was active as measured by rna transcript assays in both stem and root tissues. to determine the cell-specific expression pattern of the exta gene, a promoter-reporter gene ... | 1991 | 1912494 |
| expression of a chimaeric granule-bound starch synthase-gus gene in transgenic potato plants. | granule-bound starch synthase is the key enzyme in amylose synthesis. the regulation of this gene was investigated using a chimaeric gene consisting of a 0.8 kb 5' upstream sequence of the granule-bound starch synthase gene from potato and the beta-glucuronidase gene which was introduced into potato using an agrobacterium tumefaciens binary vector system. the chimaeric gene was highly expressed in stolons and tubers, whereas the expression in leaves, stems or roots from greenhouse-grown plants w ... | 1991 | 1912493 |
| localization and orientation of the vird4 protein of agrobacterium tumefaciens in the cell membrane. | the vird4 gene of agrobacterium tumefaciens is essential for the formation of crown galls. analysis of the nucleotide sequence of vird4 has suggested that the n-terminal region of the encoded protein acts as a signal peptide for the transport of the vird4 protein to the cell membrane of agrobacterium. we have examined the localization and orientation of this protein in the cell membrane. when the nucleotides encoding the first 30 to 41 amino acids from the n-terminus of the vird4 protein were fu ... | 1991 | 1909421 |
| mechanism of phenolic activation of agrobacterium virulence genes: development of a specific inhibitor of bacterial sensor/response systems. | the aglycone of the dihydrodiconiferyl alcohol glycosides, a series of phenolic growth factors able to substitute for some of the hormone requirements of tobacco cell division, are also potent inducers of virulence gene expression in agrobacterium tumefaciens. however, these factors do not conform to the previously established structural requirements necessary for vir expression. systematic evaluation of the structural requirements of these inducers has led to a model detailing the role of the p ... | 1991 | 1909032 |
| mutants of agrobacterium tumefaciens with elevated vir gene expression. | expression of agrobacterium tumefaciens virulence (vir) genes requires vira, virg, and a plant-derived inducing compound such as acetosyringone. to identify the critical functional domains of vira and virg, a mutational approach was used. agrobacterium a136 harboring plasmid pgp159, which contains vira, virg, and a reporter virb:lacz gene fusion, was mutagenized with uv light or nitrosoguanidine. survivors that formed blue colonies on a plate containing 5-bromo-4-chloro-3-indolyl beta-d-galactos ... | 1991 | 1908084 |
| mannopine and mannopinic acid as substrates for arthrobacter sp. strain mba209 and pseudomonas putida na513. | the characteristics of mannopine and mannopinic acid utilization by agrobacterium tumefaciens b6s3, arthrobacter sp. strain mba209, and pseudomonas putida na513 were studied. strain b6s3 utilized the four mannityl opines, mannopine, mannopinic acid, agropine, and agropinic acid. it also utilized several mannityl opine analogs, which were modified in either the sugar or the amino acid moiety. it utilized mannopine more rapidly after preincubation on mannopine, mannopinic acid, or glutamine than a ... | 1991 | 1902209 |
| survival of agrobacterium radiobacter k84 on various carriers for crown gall control. | screening was performed on nine carriers to find an improved formulation for agrobacterium radiobacter k84 cells. the survival data showed that it is possible to preserve a. radiobacter cells on dry solid supports for a long time provided that the storage temperature is 4 degrees c and that the inoculation volume for 4 x 10(9) cfu g-1 is not less than 0.15 ml g of carrier-1. on the other hand, a substantial carrier water content was necessary for room temperature storage. many materials proved t ... | 1991 | 1892394 |
| analysis of the 5' flanking region responsible for the endosperm-specific expression of a rice glutelin chimeric gene in transgenic tobacco. | the 5' upstream region of the rice storage protein type ii glutelin gene was examined for its regulatory function in transgenic tobacco. chimeric genes containing 5' flanking regions of the glutelin gene transcriptionally fused to the beta-glucuronidase (gus) reporter gene were introduced into the tobacco genome by agrobacterium tumefaciens-mediated gene transfer. the chimeric genes were expressed specifically in developing seeds, as opposed to leaves and stems, of the transgenic tobacco. histoc ... | 1991 | 1888896 |
| cytokinin content and tissue distribution in plants transformed by a reconstructed isopentenyl transferase gene. | the cytokinin gene, isopentenyl transferase (ipt), was placed under the control of a heat-inducible promoter from the drosophila melanogaster hsp70 gene and introduced into nicotiana plumbaginifolia by cocultivation with agrobacterium tumefaciens. transformants were analyzed for organ-specific expression, cytokinin levels and effects on plant development before and after the heat induction. the ipt gene transcripts were detected in leaves and stems but not roots of transgenic plants following a ... | 1991 | 1888890 |
| broad-host-range properties of plasmid rk2: importance of overlapping genes encoding the plasmid replication initiation protein trfa. | the trfa gene, encoding the essential replication initiation protein of the broad-host-range plasmid rk2, possesses an in-frame overlapping arrangement. this results in the production of trfa proteins of 33 and 44 kda, respectively. utilizing deletion and site-specific mutagenesis to alter the trfa operon, we compared the replication of an rk2-origin plasmid in several distantly related gram-negative bacteria when supported by both trfa-44 and trfa-33, trfa-33 alone, or trfa-44/98l (a mutant for ... | 1991 | 1885553 |
| stimulation of agrobacterium tumefaciens t-dna transfer by overdrive depends on a flanking sequence but not on helical position with respect to the border repeat. | t-dna transfer by agrobacterium tumefaciens depends on the right border repeat of the t-dna and is greatly stimulated by overdrive, an adjacent sequence. we report that the function of overdrive does not depend on helical position with respect to the border repeat. a synthetic 24-bp overdrive and a 12-bp region containing a fully conserved 8-bp core overdrive sequence stimulated virulence equally, but full function required additional bases to the left of the 24-bp sequence. | 1991 | 1885533 |
| auxin-induced expression of the soybean gh3 promoter in transgenic tobacco plants. | the gene encoding the auxin-responsive gh3 mrna (g. hagen, a. kleinschmidt, tj. guilfoyle, planta 162: 147-153 (1984] from soybean was cloned, and its sequence and transcription initiation site were determined. the promoter of the gh3 gene has been fused to the open reading frame of the escherichia coli uida gene which encodes beta-glucuronidase (gus). this fusion gene was introduced into tobacco via agrobacterium tumefaciens-mediated transformation, and the expression of the gene was examined b ... | 1991 | 1884011 |
| expression of a bacterial lysine decarboxylase gene and transport of the protein into chloroplasts of transgenic tobacco. | a possible approach for altering alkaloid biosynthesis in plants is the expression of genes encoding key enzymes of a pathway such as lysine decarboxylase (ldc) in transgenic plants. two strategies were followed here: one focused on expression of the gene in the cytoplasm, the other on subsequent targeting of the protein to the chloroplasts. the ldcgene from hafnia alvei was therefore (a) placed under the control of the 1' promoter of the bidirectional tr promoter from agrobacterium tumefaciens ... | 1991 | 1883998 |
| agrobacterium radiobacter peritonitis in two patients maintained on chronic peritoneal dialysis. | we report two patients with end-stage renal disease maintained on chronic peritoneal dialysis who developed peritonitis in which the infecting organism was agrobacterium radiobacter, normally a rare pathogen in humans. both patients initially responded to antibiotics, but later relapsed and required catheter removal. neither had been exposed to soil or plant material. a radiobacter is yet another of a growing list of unusual organisms that infect the peritoneal cavity of peritoneal dialysis pati ... | 1991 | 1882836 |
| isolation of agrobacterium radiobacter from a central venous catheter. | a case of septicemia caused by agrobacterium radiobacter is reported in a patient undergoing chemotherapy treatment who had recently been neutropenic. agrobacterium radiobacter was isolated from the hickman line blood culture. the patient responded favorably to removal of the hickman catheter and treatment with amikacin and piperacillin. the molecular and biochemical characteristics of the isolate are presented. | 1991 | 1874251 |
| 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 ... | 1991 | 1872613 |
| sequence of agrobacterium tumefaciens biotype iii auxin genes. | 1991 | 1868204 | |
| sequence of the iaa and ipt region of different agrobacterium tumefaciens biotype iii octopine strains: reconstruction of octopine ti plasmid evolution. | the ta regions of biotype iii octopine/cucumopine (oc) ti plasmids are closely related to the tl region of the biotype i octopine ti plasmids ptiach5 and pti15955. sequence analysis shows that the limited and wide host range biotype iii oc ta regions are derived from a common ancestor structure which lacked the 6a gene found in the biotype i octopine tl region. the ta region of the wide host range oc ti plasmids has conserved most of the original tl-like structure. in most wide host range oc iso ... | 1991 | 1868199 |
| electrophoretic separation of the three rhizobium meliloti replicons. | the megaplasmids and the chromosome from the bacterium rhizobium meliloti 1021 were separated in preparative quantities by using transverse alternating-field gel electrophoresis. the genetic content of each electrophoretically separated band was determined by southern hybridization with replicon-specific probes and by comparison with agrobacterium tumefaciens transconjugants harboring either psym-a or psym-b megaplasmids. pulsed-field gel electrophoresis analyses of paci (5'-ttaattaa-3') and swa ... | 1991 | 1860826 |
| genetic and molecular analyses of pica, a plant-inducible locus on the agrobacterium tumefaciens chromosome. | pica is an agrobacterium tumefaciens chromosomal locus, identified by mu d11681 mutagenesis, that is inducible by certain acidic polysaccharides found in carrot root extract. cloning and genetic analysis of a pica::lacz fusion defined a region of the pica promoter that is responsible for the induction of this locus. furthermore, we identified a possible negative regulator of pica expression upstream of the pica locus. this sequence, denoted pgl, has extensive homology to polygalacturonase genes ... | 1991 | 1860822 |
| 35s-beta-glucuronidase gene blocks biological effects of cotransferred iaa genes. | the iaam and iaah genes of agrobacterium tumefaciens and agrobacterium rhizogenes play an important role in crown gall and hairy root disease. the iaam gene codes for tryptophan monooxygenase which converts tryptophan into indole-3-acetamide (iam). iam is converted into the auxin indole-3-acetic acid (iaa) by indoleacetamide hydrolase, encoded by the iaah gene. in functional studies on the activity of the iaa genes of the tb region of the a. tumefaciens biotype iii strain tm4, the frequently use ... | 1991 | 1859868 |
| organization of the agropine synthesis region of the t-dna of the ri plasmid from agrobacterium rhizogenes. | the agropine/mannopine synthesis region of the tr region of the ri plasmid of agrobacterium rhizogenes strain a4 was localized on the basis of sequence similarity with probes from ti plasmids of agrobacterium tumefaciens and analysis of transposon insertions. the nucleotide sequence of the right part of the tr-dna of pria4, encompassing the three genes involved in mannityl-opine synthesis, was determined and compared to the sequence of the corresponding region of the octopine-type ti plasmid pti ... | 1991 | 1852015 |