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effect of cadmium on fungi and on interactions between fungi and bacteria in soil: influence of clay minerals and ph.fungi (rhizopus stolonifer, trichoderma viride, fusarium oxysporum f. sp. conglutinans, cunninghamella echinulata, and several species of aspergillus and penicillium) tolerated higher concentrations of cadmium (cd) when grown in soil than when grown on laboratory media, indicating that soil mitigated the toxic effects of cd. in soil amended with clay minerals, montmorillonite provided partial or total protection against fungistatic effects of cd, whereas additions of kaolinite provided little or ...197718085
agrobactin, a siderophore from agrobacterium tumefaciens.a siderophore (microbial iron transport compound) was isolated from low iron cultures of agrobacterium tumefaciens b6. the substance was characterized as a threonyl peptide of spermidine acylated with 3 residues of 2,3-dihydroxybenzoic acid, the carbonyl group of 1 residue of the latter participating in an oxazoline ring with the beta-hydroxyl of the threonine moiety. the compound, n-[3-(2,3-dihydroxybenzamido)propyl]-n-[4-(2,3-dihydroxybenzamido)butyl]-2-(2,3-dihydroxyphenyl)-trans-5-methyl-oxa ...197933987
interactions and dna transfer between agrobacterium tumefaciens, the ti-plasmid and the plant host.agrobacterium tumefaciens is a gram-negative bacterium with the unique capacity to induce neoplasmic transformations in dicotyledonous plants. recently, both the mechanism and the biological significance of this transformation have been elucidated. agrobacterium tumefaciens strains contain a large extrachromosomal dna plasmid (the ti-plasmid). this ti-plasmid is responsible for the oncogenic properties of agrobacterium strains. a particular segment of the ti-plasmid, containing information deter ...197936626
fine structure and distribution of extracellular polymer surrounding selected aerobic bacteria.the structure and distribution of extracellular polymer surrounding bacillus circulans, diplococcus (streptococcus) pneumoniae, streptococcus salivarius, staphylococcus aureus, klebsiella pneumoniae, pseudomonas aeruginosa, herella vaginacola (acinetobacter calcoaceticus), and agrobacterium tumefaciens were studied by electron microscopy. a modified ruthenium red staining procedure was used to examine the fine structure of capsule and slime. freeze-etching and critical-point drying were used to ...197546774
proceedings: studies on large dna plasmids of agrobacterium tumefaciens. 197554090
particulate cytochrome c in agrobacterium tumefaciens.in agrobacterium tumefaciens the main part of c-type cytochromes is tightly bound to the bacterial cell envelope structures. several techniques were attempted to solubilize these cytochromes. the highest yield of cytochromes released is obtained by treatment of particle suspensions with 5% triton x-100. further purification confirms that the proteins are not really solubilized, but still aggregated in small heterogeneous complexes. chromatography on a cm-cellulose column demonstrates that at lea ...197558606
purification of the agrobacterium radiobacter 84 agrocin. 197558630
[a rna extract from oncogenic and non oncogenic strains of agrobacterium tumefaciens is an indispensable element for the induction of tumors in datura stramomium].an rna bound to the reverse transcriptase of agrobacterium tumefaciens has been isolated and shown to be oncogenic for stem tissues of datura stramonium grown under axenic conditions. the tumorous nature of the cellular change induced by the infectious rna was demonstrated by serial grafts of tumors on datura stems and by cultivation of tumorous tissue in vitro on a medium without supplemental auxins and cytokinins. active cellular proliferation within tissues of datura stems was a prerequisite ...197658705
sequence of the haem-binding region of cytochrome c-556 from agrobacterium tumefaciens, strain b2a [proceedings]. 197993467
studies on regulatory functions of malic enzymes. v. comparative studies of malic enzymes in bacteria.screening of four malic enzymes--nad-linked enzyme [ec 1.1.1.38], nad, nadp-linked enzyme [ec 1.1.1.39], nadp-linked enzyme [ec 1.1.1.40], and d-malic enzyme--was carried out with cell-free extracts of the following 16 strains of bacteria by the aid of sepharose 6b column chromatography: 9 strains of enteric bacteria, 3 strains of pseudomonas, alcaligenes faecalis, agrobacterium tumefaciens, rhodospirillum rubrum, and clostridium tetanomorphum. all the strains tested contained at least one malic ...197896110
isolation of large bacterial plasmids and characterization of the p2 incompatibility group plasmids pmg1 and pmg5.large plasmids from agrobacterium tumefaciens, salmonella typhimurium, escherichia coli, pseudomonas putida, and pseudomonas aeruginosa were routinely and consistently isolated using a procedure which does not require ultracentrifugation but includes steps designed to separate large-plasmid dna from the bacterial folded chromosome. it also selectively removes fragments of broken chromosome. a variety of large plasmids was readily visualized with agarose gel electorphoresis, including five betwee ...197897269
[stimulation of induction or inhibition of crown-gall tumor development by rna-fragments u2. interference by auxin].rna-fragments u2 obtained by mild degradation with rnase u2 of ribosomal rna containing a and g nucleotides in excess are capable of exhibiting either a stimulatory effect on the induction of crown-gall tumors or an inhibitory action on their subsequent development. these different effects are dependent on the moment at which rna-fragments were introduced into wounded pea seedlings infected by agrobacterium tumefaciens b6. the results obtained in vitro and in vivo suggest that an interaction bet ...1979111819
characterization and comparison of chloramphenicol acetyltransferase variants.1. variants of chloramphenicol acetyltransferase from a variety of bacterial species have been isolated and purified to homogeneity. they constitute a heterogeneous group of proteins as judged by analytical affinity and hydrophobic ('detergent') chromatography, native and sodium dodecyl sulfate electrophoresis, sensitivity to sulfhydryl specific reagents, steady state kinetic analysis, and reaction with antisera. 2. the most striking observation is that three variants of chloramphenicol acetyltr ...1979116849
[the influence of protoplast media on the tumor induction on kalanchoe leaves].experiments concerning tumor transformation of plant cells or protoplasts need complete knowledge of the effects of media components. here inhibiting effects of cellulase onozuka, glucose, sucrose and mannitol (up to 0.3m), of tissue culture media, and of the antibiotic aureomycin on the tumor initiation process in kalanchoe leaves are reported. also the influence of these substances on the growth of the tumor inducing agrobacterium tumefaciens is studied. the results lead to the design of condi ...1975123395
[nucleic acids during tumorous transformation in plants].crown-gall, one of the "plant cancer" is induced in the presence of a soil bacterium agrobacterium tumefaciens which elaborates a tumor inducing principle (t.i.p.), the nature of which is unknown. several informations suggest that some dna sequences of bacterial origin are included in tumorous cells of tissue cultures. a ribonuclease inhibits induction. an rna extracted from agrobacterium induces some hyperplasia transplantable by graft.1975130189
[tumorous nature of hyperplasia obtained experimentally].the determination of the tumorous nature of an overgrowth provides one of the most essential information for all research concerning animal and plant cancerisation. the experimental procedure which will be described here answers to this imperative: it allows to prove the tumorous characteristics of proliferations obtained by inoculation of agrobacterium tumefaciens rna fractions to datura stems.1975130191
effect of three nematicides on the growth of some phytopathogenic bacteria and fungi.the effect of three nematicides, aldicarb, fensulfothion, and phenamiphos at four concentrations (1, 5, 25, and 125 ppm) was tested on the growth of five bacteria, agrobacterium tumefaciens, corynebacterium fascians, erwinia carotovora, pseudomonas solanacearum, and streptomyces scabies and four fungi, fusarium oxysporum f. sp. vasinfectum, fusarium solani, rhizoctonia solani, and sclerotium bataticola. of the bacteria, p. solanacearum was most affected by the chemicals at all concentrations, wh ...1977143857
in vivo transfer of the ti-plasmid of agrobacterium tumefaciens to escherichia coli.the ti-plasmids are naturally self-transmissible from their normal host agrobacterium to e. coli. they are however unable to stably establish themselves as a replicon in e. coli. it is nevertheless possible to study the ti-plasmids in e. coli with the help of ti::rp4 cointegrate plasmids that transfer and maintain themselves very efficiently in e. coli. an e. coli harbouring such a ti::rp4 plasmid is unable to catabolize octopine and unable to induce crown-gall tumours on plants.1978150536
differential toxicities of mercury to bacteria and bacteriophages in sea and in lake water.mixtures of anionic hgcl3-/hgcl4(2)-complexes were less toxic to terrestrial bacteria (erwinia herbicola, agrobacterium tumefaciens), to marine bacteria (acinetobacter sp., aeromonas sp.), and to bacteriophages (phi 11 m 15 of staphylococcus aureus and p1 of escherichia coli) than were equivalent concentrations of hg as cationic hg2+. the toxicity of 1 ppm hg to a. tumefaciens. aeromonas sp., and phi 11 m 15 was less in seawater than in lake water. inasmuch as the hg-cl species are formed in env ...1979161510
transfer of the tumor inducing factor in agrobacterium tumefaciens. 1975164858
purification and properties of cytochrome c-556 from agrobacterium tumefaciens b2a.cytochrome c-556 from agrobacterium mefaciens b2a was isolated in a pure, homoneous state. the best purification procedure volved ammonium sulphate fractionation, delting on sephadex g-25, column chromatographic fractionation on deae- and cm-cellulose, and gel filtration on sephadex g-75 superfine. substitution of the cm-cellulose step by isoelectric focusing was successful. the purity of the final preparation is warranted by the purity index value, the electrophoretic patterns in the absence an ...1975170180
soluble proteins and hydrolases during crown-gall induction in the tomato, lycopersicon esculentum.soluble proteins isolated from tissues of the tomato lycopersicon esculentum, after inoculation with agrobacterium tumefaciens to induce tumours, have been examined by gel electrophoresis and cytochemically. changes that occur include the suppression of host enzymes, the appearance of bacterial enzymes in the host tissues and the appearance of new enzyme bands in the affected cells. these changes are detectable within 6 hr of infection and prior to evident morphological changes, and may be expl ...1976178634
a ferrodoxin from agrobacterium tumefaciens. 1975179857
dna modifying enzymes of agrobacterium tumefaciens: effect of dna topoisomerase, restriction endonuclease, and unique dna endonuclease on plasmid and plant dna.extracts from agrobacterium tumefaciens strain id135 contain three enzymes that have been characterized and partially purified. the first enzyme, a dna topoisomerase, appeared to relax only negatively twisted dna. the second enzyme, atu i, a type ii restriction endonuclease, generated the identical dna digestion pattern as ecorii when several dnas were used. the third enzyme, endonuclease a, showed a preference for superhelical dnas as substrates. when plasmid pck135dna, obtained from the virule ...1978212732
polymyxin resistance in agrobacterium tumefaciens and its effect on crown gall tumor induction.polymyxin-resistant (pblr) mutants of agrobacterium tumefaciens a6, b6, and b6m were isolated from polymyxin-sensitive (pbls) parent strains in a defined medium containing 600 microgram of polymyxin b sulfate per millilitre. the weight and number of tumors induced by pblr mutants on a variety of host plants such as carrot, potato, and pinto bean were 45--75% less than those induced by pbls wild types. the crude cell envelopes (cce) prepared from both pbls and pblr bacteria were inhibitory for tu ...1979219950
a c-terminal haem-bound cytochrome c-556 from agrobacterium tumefaciens, strain b-2a. amino acid composition and n-terminal sequence analysis. 1979221262
rapid mapping of transposon insertion and deletion mutations in the large ti-plasmids of agrobacterium tumefaciens.a procedure is presented, that has allowed the rapid assignment of transposon tn1 and tn7 insertion sites in the large (130 md) nopaline ti-plasmid ptic58, to specific restriction enzyme fragments. total bacterial dna is isolated from agrobacterium tumefaciens strain c58 mutants that carry a transposon in their ti-plasmid, and digested with an appropriate restriction endonuclease. the fragments are separated on an agarose gel, denatured and transferred to nitrocellulose filters. these are hybrid ...1979231764
small-scale techniques for the analysis of recombinant plasmids.using the cloning of part of the t-dna of ptic58 from agrobacterium tumefaciens as an example, techniques are described which enable recombinant plasmids to be mapped and used as hybridization probes. in all cases the starting material is a colony of cells grown on an agar plate which is then subjected to lysis by lysozyme and triton x-100 in volumes of the order of 300 microliters thus eliminating the need for handling and centrifuging liquid cultures under restrictive containment conditions.1979233238
transposition of plasmid dna segments specifying hydrocarbon degradation and their expression in various microorganisms.the conjugative tol plasmid (75 mdal), specifying biodegradation of xylenes, toluene, and trimethylbenzene derivatives, undergoes dissociation in pseudomonas aeruginosa pao to a nonconjugative tol(*) plasmid (28 mdal) and a transfer plasmid termed toldelta (48 mdal). the tol(*) plasmid is rendered transmissible through introduction of a number of conjugative plasmids such as factor k, cam, and toldelta but not by the fp2 derivative pr0271. transfer of tol(*) via factor k or toldelta is mediated ...1978277912
proteins conferred by the virulence-specifying plasmid of agrobacterium tumefaciens c-58.membrane-associated and periplasmic proteins of agrobacterium tumefaciens c-58 were compared with those from avirulent (nontumrigenic) derivative strains by slab and two-dimensional gel electrophoresis. two proteins (per-i and per-2), with a molecular weight of 37,500 and 37,300, respectively, were detected in the supernatant fraction of cells of strain c-58 treated with edta and lysozyme in which a 117-megadalton plasmid confers virulence on the organism. the same proteins are missing in an av ...1978278990
molecular cloning as a tool to the analysis of the ti plasmids of agrobacterium tumefaciens [proceedings]. 1978289306
isolation of a recombination deficient agrobacterium tumefaciens mutant.the isolation of a recombination deficient (rec-) strain of agrobacterium tumefaciens is described. strain lba 4011 was mutagenized with nitrosoguanidine and after segregation 18,000 colonies were replica plated and uv irradiated. twentytwo uv sensitive strains were isolated and tested for methylmethanesulphonate (mms) sensitivity. six of these strains were more mms-sensitive than lba 4011. a ti plasmid that was genetically marked with tn 1 (cbr) was introduced in these strains and the rescue of ...1979290851
replica-plating virulence assay for agrobacterium tumefaciens.replica plating onto wounded tobacco leaves provides a convenient method for screening for avirulent mutants of agrobacterium tumefaciens.1977330393
the ti-plasmid of agrobacterium tumefaciens, a natural vector for the introduction of nif genes in plants? 1977336023
transfer of nitrogen fixation genes from a bacterium with the characteristics of both rhizobium and agrobacterium.strain t1k, reported to be rhizobium trifolii strain t1 carrying the drug resistance plasmid ru-1drd, was able to transfer a cluster of nif+ genes to escherichia coli k-12. additional genetic material, resembling the gal-chla region of e. coli, was also transferred from strain t1k. the segregation pattern of these transferred genes suggested that they were on a plasmid. although strain tik was able to nodulate red and white clover, it also formed very slow-growing galls on tomato stems and share ...1978342496
transfection and transformation of agrobacterium tumefaciens.the freeze thaw transfection procedure of dityatkin et al. (1972) was adapted for the transfection and transformation of a. tumefaciens. transfection of the strains b6s3 and b6-6 with dna of the temperate phage ps8cc186 yielded a maximum frequency of 2 10(-7) transfectants per total recipient population. in transformation of the strain gv3100 with the p type plasmid rp4 a maximum frequency of 3.5 10(-7) transformants per total recipient population was obtained. agrobacterium ti-plasmids were int ...1978355847
transfer of rp4::mu plasmids to agrobacterium tumefaciens. 1978372975
crown-gall and agrobacterium tumefaciens: survey of a plant-cell-transformation system of interest to medicine and agriculture. 1979377583
transcription of ti plasmid-derived sequences in three octopine-type crown gall tumor lines.total rna isolated from three octopine-type crown gall lines contains sequences homologous to specific regions of the tumor-inducing (ti) plasmid of agrobacterium tumefaciens strain 15955. a comparison of transcripts in these three tumor lines suggests that tumor cells transcribe various sequences within a sector of plasmid dna of 13 x 10(6) daltons and that transcription may not be uniform across the plasmid derived sequences (t-dna). transcription of t-dna by octopine-type tumors occurs at fou ...1979379864
primary structure of a chloramphenicol acetyltransferase specified by r plasmids.naturally occurring isolates of chloramphenicol-resistant bacteria commonly synthesise chloramphenicol acetyltransferase (ec 2.3.28; cat) in amounts which are sufficient to account for the resistance phenotype and often harbour plasmids which carry the structural gene for cat. the findings of cat in such diverse prokaryotes as proteus mirabilis, agrobacterium tumefaciens, streptomyces sp., and a soil flavobacterium has led to speculation concerning the origin and evolution of the more commonly o ...1979390404
tumor induction by agrobacterium tumefaciens prevented in vigna sinensis seedlings systemically infected by ribonucleic acid viruses.cowpea (vigna sinensis) seedlings failed to develop tumors after being inoculated with crown gall bacteria (agrobacterium tumefaciens) if, at times earlier than 1 day later, they were inoculated on the primary leaves with a cowpea mosaic virus that systemically infects them. inoculation with buffer or with a virus that is restricted to a localized infection, or to which the cowpea is immune, did not interfere with the subsequent development of tumors. the virus infection did not appear to affect ...1979422243
crown gall teratoma formation is plasmid and plant controlled.experiments using different species of the plant nicotiana and strains of the bacterium agrobacterium tumefaciens showed that teratoma formation from crown galls was dependent on the combination of bacterial ti plasmid and host plant used.1979422509
isolation of a non-tumor-inducing mutant of the ti plasmid of agrobacterium tumefaciens strain b6.a nonpathogenic mutant of agrobacterium tumefaciens strain b6 was isolated and its properties compared with the parental strain in an effort to localize the mutation. both b6 and its mutant (b6-95) had similar colony color and morphology, were ketolactose positive, utilized octopine, and contained plasmid dna. kinetic analysis of dna reannealing showed that total dna homology and plasmid dna homology between b6 and b6-95 was at least 90%. the length of both plasmids was found to be 58 micrometer ...1979455147
genetic mapping of the bacteriophage ps8 of agrobacterium tumefaciens.genetic mapping of the chromosome of the bacteriophage ps8 of agrobacterium tumefaciens using temperature sensitive (ts) mutants of the bacteriophage is described.1979456950
r-plasmid-mediated chromosomal gene transfer in agrobacterium tumefaciens.although several techniques are available for transferring the ti plasmids from one strain of agrobacterium tumefaciens to another, there are no reproducible methods for analysis of chromosomal markers in this phytopathogen. the r plasmid, r68.45, is known to show chromosomal mobilizing ability in several bacterial genera including the closely related rhizobia. r68.45 was transferred into the prototrophic a. tumefaciens strain 15955. ten kanamycin-resistant transconjugant clones were tested for ...1979457601
negative control of octopine degradation and transfer genes of octopine ti plasmids in agrobacterium tumefaciens.the regulatory system that controls the expression of the ti plasmid-borne octopine degradation (uad) and transfer (tra) genes in agrobacterium tumefaciens was studied. a deletion mutant derived from the cointegrate plasmid r702::ti-b6s3 was isolated, which was compatible with a wild-type ti plasmid and which had retained the uad genes. by means of this mutant plasmid pal116, it was possible to make cells diploid for the uad genes. pal116 was introduced into rec- strains that contained different ...1979457610
host range conferred by the virulence-specifying plasmid of agrobacterium tumefaciens.the host range of agrobacterium tumefaciens 1d1109, known to induce crown gall only on grapevine (vitis spp.), was extended to include many plant species by transferring a tumor-inducing plasmid (pti) from strain 1d1, a broad-host-range pathogen. the pti plasmid was mobilized by the conjugative plasmid prk2, which was inserted into 1d1 by mating with escherichia coli j53(prk2). the resulting transconjugants were screened for their ability to induce crown gall tumors on hosts other than grapevine ...1979457613
choriogonadotropin-like antigen in an anaerobic bacterium, eubacterium lentum, isolated from a rectal tumor.using the indirect fluorescein-labeled and indirect peroxidase-antiperoxidase-labeled immunohistochemical techniques, and utilizing both antiserum specific for the beta-subunit of choriogonadotropin and antiserum for the total hormone, we have demonstrated the presence of a choriogonadotropin-like immunoreactive material in a strain of eubacterium lenthum that was originally isolated from a rectal tumor. in contrast, both immunohistochemical reactions were negative when applied to a strain of co ...1979468380
purification and characterization of the crown gall specific enzyme nopaline synthase.nopaline synthase of sunflower (helianthus annuus l.) crown gall tissue induced by agrobacterium tumefaciens strain c58 or t37 (nopaline utilizers) was purified to homogeneity as judged by analytical disc gel electrophoresis. the native enzyme elutes from a column of ultrogen aca 34 as a single peak with an estimated molecular weight of 158,000. the dissociated enzyme migrates on nadodso4-polyacrylamide gels as a single band with a molecular weight of 40,000. thus, the native enzyme appears to b ...1979476084
purification and properties of d-glucosaminate dehydratase from agrobacterium radiobacter. 1979477973
a new site-specific endonuclease showing phenotypical crypticity in a tumorigenic strain of agrobacterium tumefaciens.atubvi, an endonuclease showing new site-specificity, has been isolated from the tumorigenic strain iibv7 of agrobacterium tumefaciens, and is undetectable in the non-tumorigenic sister strain iibnv6. atubvi degrades iibv7 dna in vitro and should, therefore, be regarded as being phenotypically cryptic in the bacterial cell; it also shows anomalous behavior under cerain incubation conditions. these properties point to a possible role for this enzyme in the insertion of exogenous ti-plasmid dna in ...1979478298
indoleacetic acid production: a plasmid function of agrobacterium tumefaciens c58. 1979496970
purification and characterization of agrocin 84.a procedure for the rapid purification of milligram quantities of agrocin 84, a bacteriocin-like compound produced by agrobacterium radiobacter strain k-84, has been developed. this procedure, which employs charcoal adsorption, ion-exchange, sieving chromatography, and continuous-flow electrophoresis, can yield agrocin 84 which is 65% pure on a dry weight basis. the purest preparations were strongly ultraviolet absorbing, with a maximum at 264 nm (epsilon 7.0/264 = 22,675 cm2 - m-1) and a minimu ...1979507786
a study of the tumorogenesis of agrobacterium tumefaciens conn. on some plant species of iran.this paper is a survey and comparative type of study on the tumorogenetic effect of agrobacterium tumefaciens on some plant species of iran. the results obtained indicate that the tumor-inducing property of this micro-organism is not common to all plant species studied; moreover no tumor was initiated on the mature leaves by the bacteria. the results obtained with the local varieties of the susceptible plants show some qualitative and quantitative differences as compared with the works of other ...1979545942
crown gall: economic importance and control.many plants of economic importance are possible hosts for agrobacterium tumefaciens, the causal organism of the crown gall tumor disease. damage has been reported on stone fruit (australia), vineyard (hungary, bulgaria), lettuce (brasil) ... in western-europe, crown gall seems to be of less economic importance for plants growing in the open air. however, plants cultivated in greenhouses have a greater chance to be tumorized, because of the more favourable circumstances for tumor induction. moder ...1979549390
coordinated regulation of octopine degradation and conjugative transfer of ti plasmids in agrobacterium tumefaciens: evidence for a common regulatory gene and separate operons.by using the analog noroctopine, mutants of agrobacterium tumefaciens were isolated with altered regulation patterns for the ti plasmid-borne octopine utilization genes. these could be divided into three classes: (i) strains with a constitutive level of octopine enzymes and a high degree of spontaneous ti transfer; (ii) one strain with constitutive octopine enzymes but no spontaneous ti transfer; and (iii) strains with an altered inducibility in which, contrary to the wild-type ti plasmid, conju ...1978711678
[ring structures on the cell wall of agrobacterium tumefaciens (author's transl)]. 1978713041
multiple genes coding for octopine-degrading enzymes in agrobacterium.most biotype 2 strains of agrobacterium tumefaciens and a. radiobacter which utilize nopaline also degrade octopine. in all such strains studied, the ability to degrade octopine did not appear to be transferred to plasmidless recipient cells under conditions of plasmid transfer in which the ability to utilize nopaline was transferred. an octopine-degrading mutant was isolated in a strain cured of its plasmid, suggesting that genes of octopine degradation may have a chromosomal location in some s ...1978721779
[proliferative activity of normal and tumorous plant tissues cultivated in vitro].proliferative pools of helianthus tuberosus l. explants tissues were studied using autoradiography with 3h-thymidine in the course of normal growth in vitro and tumorous growth induced by agrobacterium tumefaciens. it is determined that on the 3d or 4th day of tumorous transformation the number of cycling cells reaches 30% whereas that of normally growing explants showed 10-11%. no changes were observed in 3h-thymidine transport during this period.1978726052
plasmid-dependent attachment of agrobacterium tumefaciens to plant tissue culture cells.kinetic, microscopic, and biochemical studies show that virulent ti (tumor inducing)-plasmid-containing strains of agrobacterium attach to normal tobacco and carrot tissue culture cells. kinetic studies showed that virulent strains of a. tumefaciens attach to the plant tissue culture cells in increasing numbers during the first 1 to 2 h of incubation of the bacteria with the plant cells. five ti-plasmid-containing virulent agrobacterium strains showed greater attachment to tobacco cells than did ...1978730370
mutagenesis by insertion of the drug resistance transposon tn7 applied to the ti plasmid of agrobacterium tumefaciens. 1978748948
restriction endonuclease mapping of a plasmid that confers oncogenicity upon agrobacterium tumefaciens strain b6-806. 1978748950
production of adventitious root primordia on hypocotyls of castor bean seedling, infected with agrobacterium tumefaciens.the development of sterile secondary tumours on hypocotyls of castor bean seedlings, inoculated with any of the ten isolates of agrobacterium tumefaciens tested, were observed below the site of the primary tumours. histopathological studies performed in the present work indicate that the observed secondary tumours were adventitious root primordia and not the ordinary type of secondary tumours. according to the available literature such findings are reported here for the first time. all the teste ...1978749411
transfer, maintenance, and expression of bacterial ti-plasmid dna in plant cells transformed with a. tumefaciens.the mechanism of induction of the plant cancer crown gall by agrobacterium tumefaciens has been briefly described. the salient points are as follows. 1. large plasmids of molecular weight (100 to 150) s 10(6), called ti-plasmids, are essential to the transformation process. 2. ti-plasmids carry a dna segment that can be transferred to, and maintained and expressed in, transformed plant cells. 3. this dna segment has been identified both by direct hybridization experiments between ti dna fragment ...1977754869
effect of sublethal heat injury on tumour induction and rna synthesis in agrobacterium tumefaciens.when cells of agrobacterium tumefaciens are subjected to sublethal heat injury at 45 degrees c for 20 min, less than 5% of the viable population retain their ability to initiate tumour formation on kalanchöe daigremontiana. if the cells are then incubated in phosphate buffer at 27 degrees c for 2 h, tumour initiation returns to control levels. inhibitors of dna and protein synthesis had little effect on the recovery of tumour initiation after heat injury. rifamycin, a specific inhibitor of rna s ...1978756950
low-intensity microwave radiation and the virulence of agrobacterium tumefaciens strain b6.when virulent cells of agrobacterium tumefaciens strain b6 were exposed to low-level microwave radiation at a frequency of 10,000 mhz and an intensity of 0.58 mw/cm2 for 30 to 120 min, a 30 to 60% decrease in their ability to produce tumors on potato and turnip disks was observed. this microwave exposure did not affect the viability of these bacteria or their ability to attach to a tumor-binding site nor did it induce thermal shock. this loss of virulence was reversible within 12 h.1979760631
conjugation in agrobacterium tumefaciens in the absence of plant tissue.a general, reliable conjugation system for agrobacterium tumefaciens in the absence of plant tissue is described in which a. tumefaciens can serve either as the donor or recipient of plasmid deoxyribonucleic acid with reasonable efficiency. plasmid rp4 was transferred from escherichia coli to a. tumefaciens and from strain of a. tumefaciens. both rp4 and the a. tumefaciens virulence-associated plasmids were detected by alkaline sucrose gradients in a. tumefaciens strains a6 and c58 after mating ...1976783141
particular small size rna and rna fragments from different origins as tumor inducing agents in datura stramonium.particular rna fragments obtained by action of pancreatic ribonuclease on purified rnas originating from species totally unrelated to agrobacterium tumefaciens (escherichia coli, rabbit, monkey) are capable of inducing the formation of transplantable tumorous tissue when introduced at wounded sites in inverted stems of datura stramonium maintained under axenic conditions on a medium containing auxin and kinetin. reovirus rna and a small size rna (5-6s) isolated from rna bound rna directed dna po ...1976822281
octopine and nopaline metabolism in agrobacterium tumefaciens and crown gall tumor cells: role of plasmid genes.crown gall tumors produced octopine or nopaline or neither compound, depending on the bacterial strain that incited the tumor. the genes specifying production of octopine or nopaline by the tumor were transferred to recipient bacterial strains when the large plasmid associated with virulence was transferred by either conjugation or deoxyribonucleic acid-mediated transformation. our results, which confirm the work of others (bomhoff et al., 1976; goldman et al., 1968; petit et al., 1970), indicat ...1977830636
plasmids in avirulent strains of agrobacterium.twelve strains of agrobacterium radiobacter isolated from naturally occurring crown galls or soil were found to be avirulent on sunflower, tomato, kalanchoe, and carrot. eleven strains contained plasmids of molecular weights 77 x 10(6) to 182 x 10(6) as determined by electron microscopy. one strain contained only a smaller plasmid (50 x 10(6) daltons). several strains had both large and small (ca. 11 x 10(6) daltons) plasmids; one strain contained two large plasmids (112 x 10(6) and 136 x 10(6) ...1977830650
induction of d-aldohexoside:cytochrome c oxidoreductase in agrobacterium tumefaciens.d-aldohexopyranoside:cytochrome c oxidoreductase (aco) was strongly induced by cellobiose, alpha-methylglucoside, beta-methylglucoside, kojibiose, and sophorose. induction was rapid, and aco was readily detectable within 10 min after addition of cellobiose as inducer. although not measurable for 30 to 40 min after addition of inducer, once started, the rate of induction with alpha-methylglucoside equaled or even exceeded that obtained with cellobiose. induction by sucrose, maltose, alpha-alpha-t ...1977838689
comparison of thirty-seven strains of vd-3 bacteria with agrobacterium radiobacter: morphological and physiological observations.thirty-seven cultures of vd-3 bacteria, isolated from clinical specimens, were characterized morphologically and physiologically. the cultures produced positive reactions when tested for oxidase, urease, nitrate reduction, phenylalanine deaminase, oxidative metabolism of carbohydrate substrates, and 3-ketolactose production. these peritrichously flagellated microorganisms were isolated primarily from the respiratory tract. when compared to authentic strains of agrobacterium, they appeared to be ...1977845244
[effect of inhibitors of transcription on the growth of mycoplasma and agrobacterium tumefaciens 8628]. 1977865316
[avirulent mutants of agrobacterium tumefaciens 8628 resistant to alpha-amanitin]. 1977865330
zeatin ribonucleosides in the transfer ribonucleic acid of rhizobium leguminosarum, agrobacterium tumefaciens, corynebacterium fascians, and erwinia amylovora.until recently, the presence in transfer ribonucleic acid (trna) of the hydroxylated cytokinin ribosylzeatin [n6-(4-hydroxy-3-methylbut-2-enyl)adenosine]was thought to be unique to higher plants. this extension of work from several laboratories indicates the presence of 2-methylthioribosylzeatin in the trna of the plant-associated bacteria rhizobium leguminosarum, agrobacterium tumefaciens, and corynebacterium fascians, but not in that of erwinia amylovora. this cytokinin has the cis configurati ...1977893341
a restriction endonuclease from agrobacterium tumefaciens. 1977913578
homology between ti-plasmids of agrobacterium tumefaciens: hybridzation studies using electron microscopy [proceedings]. 1977913837
comparative study of ti-plasmids in agrobacterium tumefaciens by use of restriction enzymes [proceedings]. 1977913838
[a study of six cultures of "agrobacterium tumefaciens" and "a. radiobacter" (author's transl)]. 1977921138
studies on agrobacterium tumefaciens. viii. avirulence induced by temperature and ethidium bromide.when tumorigenic strains of agrobacterium tumefaciens were subcultured at temperatures between 31.5 and 37 degrees c or in broth containing ethidium bromide, they lost their capacity to induce tumors in tomato plants. the sensitivities of curing virulence (tumorigenicity) depended on the density of the population of cells, fewer cells (100/ml) being more sensitive to curing than higher densities (10(6)/ml). the loss of virulence need not require the total loss of the virulence-specifying plasmid ...1977922605
plasmid content and tumor initiation complementation by agrobacterium tumefaciens iibnv6.avirulent strains iibnv6 and nt1, derived from virulent strains of agrobacterium tumefaciens, were tested for their ability to enhance tumor initiation (complement) on coinoculation with tumorigenic strains. strain nt1, cured of the agrobacterium virulence plasmid, failed to complement when inoculated with its virulent parental strain or with other virulent strains. strain iibnv6, however, complemented with all virulent strains tested. attachment to host wound sites by both strain iibnv6 and the ...1977924973
octopine and nopaline synthesis and breakdown genetically controlled by a plasmid of agrobacterium tumefaciens.several nopaline degrading strains and one octopine degrading strain are shown to loose oncogenicity as well as the ability to utilize these guanidine compounds when they are cured of their ti plasmid. to investigate whether the specific genes involved in the utilization of one or the other compound are located on the plasmid, plasmid-transfer experiments have been performed. the plasmid from a nopaline degrading strain has been transferred to a naturally non oncogenic agrobacterium namely a. ra ...1976934053
occurrence of trans-ribosylzeatin in agrobacterium tumefaciens trna. 1976934334
the presence of agrobacterium tumefaciens plasmid dna in crown gall tumour cells. 1976956781
rp4 promotion of transfer of a large agrobacterium plasmid which confers virulence.introduction of rp4 plasmid into agrobacterium tumefaciens promotes the transfer on solid medium of large virulence-associated plasmids from virulent donor strains to a plasmidless avirulent recipient. exconjugants were selected for the ability to utilize octopine or nopaline as the sole source of arginine, traits which are coded for by virulence-associated plasmids in the strains employed here. all exconjugants retained the arginine auxotrophy of the recipient strain, and were resistant to ampi ...1976971805
physical characteristics of dna from bacteriophages of agrobacterium tumefaciens.dna was extracted from isolates of bacteriophages grown on virulent and avirulent strains of agrobacterium tumefaciens. molecular weights of dna from phages isolated from the virulent a. tumefaciens (iibv7) were about 41.5 x 10(6) daltons, while those from the avirulent a. tumefaciens (iibnv6) were about 32.5 x 10(6) daltons. the buoyant densities of the four dna's ranged from 1.7086 to 1.7089 g/cm3, values that were not significantly different. dna-dna hybridization studies also indicated that ...1976974908
isoenzymes of acid phosphatase and non-specific esterases in cultures of neoplastic and normal tobacco tissues.axenic cultures of normal, habituated and crown gall teratoma were grown under varying conditions to examine the effects of environment on the expression of neoplastic character. acid phosphatase patterns on polyacrylamide gels did not vary greatly among tissues although there were differences in acid phosphatase activity between various strains of agrobacterium tumefaciens, the bacteria which cause crown gall. certain esterase isoenzymes were found only in tissues grown on specific media, while ...1976976652
properties of the cured oncogenic strain 37400 of agrobacterium tumefaciens.the properties of the 37400 oncogenic strain of agrobacterium tumefaciens are described. this strain was derived from the vi lysogenic strain originally isolated by hamilton from a zinnia elegans tumour. strain 37400 has a number of properties which render it suitable for quantitative and genetic studies. it is cured of prophages and can serve as a universal sensitive indicator for a number of phages isolated from various lysogenic strains of agrobacterium tumefaciens. its good growth properties ...1976976880
isolation and complementation analysis of temperature-sensitive mutants of the ps8 bacteriophage of agrobacterium tumefaciens. 1976976881
isolation and characterization of agrobacterium tumefaciens mutants affected in the utilization of octopine, octopinic acid and lysopine.using an enrichment procedure, mutant strains of agrobacterium tumefaciens were isolated that lacked the ability to utilize octopine as a nitrogen source. of 55 such isolates, 44 were unable to utilize several amino acids; the remaining 11 strains were altered solely in their ability to utilize octopine, octopinic acid and lysopine. it is concluded that only the latter were plasmid mutations. among them, there was a high, but no absolute, correlation with avirulence. all strains contained the t1 ...1976978177
[animal and plant cancers produced by viruses and bacteria].in this review the animal and plant cancers produced by viruses : (onkeorna, adeno, herpes, papova, pox, reovirus, fig 1-6), bacteria : (agrobacterium tumefaciens, fig. 7), fungi : (plasmodiophora brassicae, and nematode : (meloidgyne) are discussed.1976979708
[relationship between crown-gall plant tumors and the cell cycle].it is established that under conditions of the culture in vitro the greatest amount of crown-gall swellings on topinambur and carrot explants is formed with agrobacterium tumefaciens inoculation 4 and 6 hrs after the tissue extraction and planting, which corresponds to the g1-phase of the 1st cellular cycle. in the inoculated tissue cells entrance to the s-phase is accelerated and the maximal number of labelled nuclei is found 10 hrs earlier.1976982581
chemical nature of agrocin 84 and its effect on a virulent strain of agrobacterium tumefaciens.agrocin 84, produced by agrobacterium radiobacter k84, inhibited ribonucleic acid, deoxyribonucleic acid, and protein synthesis and amino acid transport in a susceptible, virulent strain of a. tumefaciens h-38-9. cell motility was immediately stopped by action of the agrocin, 50% of the cells were killed within 15 min of contact, and the remainder were inhibited. agrocin 84 is trypsin and pepsin resistant, but chemical analysis indicated a small peptide with a molecular weight of 2,500 containin ...1976984792
[the presence of agrobacterium tumefaciens in lucerne root nodules].agrobacterium tumefaciens does not penetrate into nodules on the roots of lucerne with the active strain of nodule bacterium as was established with the aid of genetic markers and plant selection. a nodule, whose shape was not typical and which did not fix nitrogen, was formed on the root of lucerne inoculated with the culture of agrobacterium tumefaciens treated with uv. a bacterial strain isolated from the nodule was identical to a. tumefaciens according to its resistance to streptomycin and s ...19761004260
trans-zeatin in culture filtrates of agrobacterium tumefaciens. 19761027440
studies on the bacteriophage ps8 of agrobacterium tumefaciens (smith and townsend) conn: physico-chemical properties of its dna.dna from the bacteriophage ps8 was extracted and purified. the buoyant density was determined was 1.716 cm3/g. the guanine-cytosine content was calculated to be 57%. dna molecules which looked like circles were found among linear strands in an electron-microscopic study. with an endonuclease from streptomyces albus g the dna was digested to 19 fragments, with molecular weights ranging from 600 to 7,400 daltons. the molecular weight of the dna was determined to be 38.8 x 10(6) daltons +/- 8.7%.19761031838
l-sorbose metabolism in agrobacterium tumefaciens.the pathway of l-sorbose metabolism in agrobacterium tumefaciens strain b6 was determined to be: l-sorbose leads to d-glucitol (sorbitol) leads to d-fructose leads to d-fructose-6-phosphate leads to d-glucose-6-phosphate. the reduction of l-sorbose and the oxidation of d-glucitol were mediated by nadph- and nad+-linked oxidoreductases, respectively. the intermediates, d-glucitol and d-fructose, were isolated from in vitro reaction mixtures by column chromatography on dowex 1-borate, and identifi ...19761085123
an enrichment technique for auxotrophs of agrobacterium tumefaciens using a combination of carbenicillin and lysozyme.a procedure to enrich for auxotrophic and fermentation mutants of agrobacterium tumefaciens is described. the method is based on the amplification of the killing power of carbenicillin by the addition of lysozyme. isolation frequencies of some types of mutants are presented, with and without the application of the proposed procedure. the yield of mutants is usually enhanced a hundredfold per enrichment treatment.19751104767
attempts to induce tumours with nucleic acid preparations from agrobacterium tumefaciens.nucleic acid preparations from agrobacterium tumefaciens (smith & townsend) conn. have been tested for tumorigenic activity on a number of bioassay systems including carrot root explants, sunflower and tobacco stem segments, callus cultures of sunflower, tobacco and carrot, and sunflower stems. the methods used to isolate and test the dna included those which have been reported to be successful for the induction of tumours. strict precautions were taken to ensure that the dna samples used in the ...19751113080
host-phage interaction on agrobacterium tumefaciens. iv. phage-directed protein synthesis.gel electrophoretic and autoradiographic techniques were used to detect the temporal sequence of protein synthesis after infection of the sensitive strain agrobacterium tumefaciens with phage lv-1. three classes of protein were detected: early proteins, class i, which include a protein capable of shutting off host protein synthesis; class ii, proteins which are detected after 30 min; and late proteins, class iii, which include the phage-directed endolysin and five additional proteins that appear ...19751113375
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