| [separation into components and recombination of nitrogenase from lupine bacteroids]. | | 1976 | 947717 |
| nitrogenase activity and respiration of cultures of rhizobium spp. with special reference to concentrations of dissolved oxygen. | studies of nitrogenase in cultures of the cowpea rhizobia (rhizobium spp.) strains 32h1 and cb756 are reported. preliminary experiments established that, even when agar cultures were grown in air, suspensions of bacteria prepared anaerobically from them were most active at low concentrations of free dissolved o2. consequently, assays for activity used low concentrations of o2, stabilized by adding the nodule pigment leghaemoglobin. in continuous, glutamine-limited cultures of 32h1, nitrogenase a ... | 1976 | 953022 |
| the presence of agrobacterium tumefaciens plasmid dna in crown gall tumour cells. | | 1976 | 956781 |
| reduction of acetylene by stationary cultures of free-living rhizobium sp. under atmospheric oxygen levels. | the reduction of acetylene to ethylene by stationary (non-shaking) cultures of free-living rhizobia under atmospheric oxygen levels has been demonstrated. under these conditions the development of the activity is inhibited by 10 mm nh4cl and about 20% of oxygen is required for maximal activity. when the stationary cultures were shaken, oxygen concentrations of 1% and higher were found to be inhibitory. specific activities of 20 and 40 nmol of acetylene reduced h-1 mg-1 protein were observed. | 1976 | 963617 |
| monomethyl sugars in extracellular polysaccharides from slow-growing rhizobia. | | 1976 | 963704 |
| adsorption of bacteria to roots as related to host specificity in the rhizobium-clover symbiosis. | quantitative microscope techniques were utilized to examine the adsorption of rhizobial cells to clover root hairs. adsorption of cells of noninfective strains of rhizobium trifolii or infective r. meliloti strains to clover root hairs was four to five times less than that of the infective r. trifolii strains. attachment of the rod-shaped bacteria to clover root cells occurred in a polar, end-on fashion. viable or heat-killed r. trifolii cells precoated with a clover lectin having 2-deoxyglucose ... | 1976 | 970936 |
| 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 ... | 1976 | 971805 |
| 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 ... | 1976 | 974908 |
| 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 ... | 1976 | 976652 |
| 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 ... | 1976 | 976880 |
| isolation and complementation analysis of temperature-sensitive mutants of the ps8 bacteriophage of agrobacterium tumefaciens. | | 1976 | 976881 |
| plasmid deoxyribonucleic acid in rhizobium trifolii. | in deoxyribonucleic acid of rhizobium trifolii centrifuged in cesium chloride-ethidium bromide equilibrium was found a sattelite peak containing covalently closed circular deoxyribonucleic acid. the plasmid had a molecular weight of about 64 x 10(6) shown by sedimentation in sucrose gradients and electron microscopy. | 1976 | 977542 |
| 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 ... | 1976 | 978177 |
| the origin of endosymbiotic nitrogen fixation by rhizobium. | | 1976 | 979293 |
| [chemistry of denitrification in sporogenous soil bacteria]. | soil sporeforming denitrifying bacteria, bacillus filaris and bacillus polymyxa, differ by their cultural-morphological and physiological characteristics, but are similar in the chemistry of dissimilating nitrate reduction. two processes occur simultaneously: denitrification yielding gaseous nitrogen forms, and nitrate respiration upon which nitrates are reduced to ammonia. the ratio between the two depends on physico-chemical conditions of the environment. the chemistry of dissimilating nitrate ... | 1976 | 979677 |
| homology between ti-plasmids of agrobacterium tumefaciens: hybridzation studies using electron microscopy [proceedings]. | | 1977 | 913837 |
| comparative study of ti-plasmids in agrobacterium tumefaciens by use of restriction enzymes [proceedings]. | | 1977 | 913838 |
| [a study of six cultures of "agrobacterium tumefaciens" and "a. radiobacter" (author's transl)]. | | 1977 | 921138 |
| [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. | 1976 | 982581 |
| 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 ... | 1976 | 984792 |
| regulation of nitrogen fixation in rhizobium sp. | regulation of nitrogen fixation by ammonium and glutamate was examined in rhizobium sp. 32h1 growing in defined liquid media. whereas nitrogenase synthesis in klebsiella pneunoniae is normally completely repressed during growth on nh4+, nitrogenase activity was detected in cultures of rhizobium sp. grown with excess nh4+. however, an "ammonium effect" on activity was invariably observed in cultures grown on nh4+ as sole nitrogen source; the nitrogenase activity was, depending on conditions, 14 t ... | 1976 | 984826 |
| ineffective and non-nodulating mutant strains of rhizobium japonicum. | mutant strains of rhizobium japonicum that were unable to allow the corsoy cultivar of soybean to reduce acetylene or fix n2 were isolated. these strains grow as well as the wild type in a variety of media. mutant strains sm1 and sm2 did not form nodules on the host plant; however, they reduced acetylene in the nonsymbiotic assay. strains sm3 and sm4 produced nodules that did not have the characteristic pink pigment caused by leghemoglobin. the nodules formed by these strains also were small. on ... | 1976 | 986388 |
| rhizobium japonicum derivatives differing in nitrogen-fixing efficiency and carbohydrate utilization. | four derivatives of rhizobium japonicum 110 were isolated on the basis of morphologically different colonies formed on yeast extract-mannitol-hm salts medium. all are able to nodulate lee soybeans. the bacteria-plant associations formed by each clone have measurable acetylene-reducing activity, but those formed by two of these clones (designated l1-110 and l2-110) are 5- to 10-fold less efficient than those formed by the others (designated i-110 and s-110). these derivatives were not detectable ... | 1976 | 988784 |
| effectiveness of rhizobia from wild species of arachis on the cultivated species, a. hypogaea and their physiological characteristics. | | 1976 | 989215 |
| root exudation in relation to innoculation with rhizobia. | | 1976 | 989216 |
| biochemical changes in the roots of legumes upon inoculation. | | 1976 | 989217 |
| nitrogen fixation by microbial cultures with sodium salt of organic acids as carbon source. | the best source of carbon, when used as the sodium salt of organic acids, is sodium salicylate which shows highest nitrogen fixation and also appreciably large amounts of nitrogen fixed per g carbon consumed. next in order is sodium benzoate, then oxalate. sodium citrate is followed by sowium acetate in the order of decreasing efficiency. | 1976 | 989656 |
| nitrate reductase from anaerobically grown rhizobium japonicum. | the activity of nitrate reductase in rhizobium japonicum is controlled by oxygen tension, and not by nitrate. the enzyme from r. japonicum grown anaerobically in the presence of nitrate resembles that from bacteroids in having a molecular weight of about 69000 daltons; the enzyme from aerobically grown cells ahs a molecular weight of about 170000 daltons. both types of enzyme have similar km values, but differ in their sensitivity to kcn. | 1976 | 993777 |
| [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 ... | 1976 | 1004260 |
| [transformation as a method for increasing the activity of lucerne nodule bacteria]. | transformation of lucerne nodule bacteria was tried as a method for increasing their activity. about 100 strains resistant to 1000 units/ml of streptomycin have been obtained by transformation; 34 strains were tested for the activity of nitrogen fixation in conditions of a microvegetative experiment according to the scheme: strain-donor, strain-recipient, transformed strains. the activity varied within a wide range: +/-30--40% cf. the activity of the parent strains. the transformed strains were ... | 1976 | 1004274 |
| [molecular nitrogen fixation by rhizobium in association with tobacco and wheat cells]. | | 1976 | 1009823 |
| [lipopolysaccharides of rhizobium lupini in its symbiotic form]. | | 1976 | 1009837 |
| characterization of soluble and structural proteins of rhizobium cells and bacteroids from root nodules. | | 1976 | 1010553 |
| characterization of ribosomal rna & proteins from rhizobium cells, bacteroids & phaseolus aureus roots. | | 1976 | 1010576 |
| [role of leguminous plants in effective symniosis with nodule bacteria]. | experiments were conducted with five clover varieties and six lucerne varieties infected with their specific strains of nodule bacteria with a high or low activity. the role of plants in active symbiosis with nodule bacteria was established. the nitrogen fixing activity of nodule bacteria varied within a wide range depending on the plant variety. not only the activity of the strain, but the variety of the plant too, should be taken into account for industrial purposes. | 1976 | 1012047 |
| [survival of rhizobium meliloti in soil studied by genetic labeling]. | the number of cells of a mutant of rhizobium meliloti resistant to streptomycin decreased to 10(6) per 1 g of soil during 3-5 days and remained at this level for at least a month when 10(8) cells of the mutant per 1 g were introduced into non-sterile soil. factors causing such a stability of the population are discussed. | 1976 | 1012051 |
| isolation of 3-o-methyl-d-ribose from a rhizobium polysaccharide. | | 1976 | 1016992 |
| trans-zeatin in culture filtrates of agrobacterium tumefaciens. | | 1976 | 1027440 |
| 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%. | 1976 | 1031838 |
| effect of some pesticides on the efficiency of the inoculated rhizobium associated with broad bean plants. | the effect of some pesticides on the efficiency of the inoculated rhizobium in broad bean plants (vicia faba) was studied in greenhouse experiments. different pesticides were used in this work, including insecticides, herbicides, nematocides, and a molecide in different concentrations. the study revealed the following conclusions. application of insecticides in different concentrations generally affected the formation of efficient nodules on the root system of broad bean plants. the inhibitory e ... | 1976 | 1037049 |
| effect of phosphate fertilization and seed inoculation with ""okadin'' at high rate on yield of broadbean and lentil. | the effect of phosphate fertilization and seed inoculation with ""okadin'' preperation of rhizobia strains on the yield of broadbean and lentil was tested in field experiments during the seasons 1969 to 1972 in the farm of faculty of agriculture, assiut university. superphosphate was added at the rate of 0, 50, 100, or 200 kg/fa., and ""okadin'' preparation, specific for the kind of legume planted, was applied to the seeds at 10 times the recommended rate. application of superphosphate at any of ... | 1976 | 1037057 |
| [factors of multiple resistance to antibiotics in nodule bacteria]. | multiple resistance to antibiotics (penicillin, levomycetin, neomycin, tetracycline) was found in 15% of collection strains of nodule bacteria and in strains isolated from natural environment. | 1976 | 1050635 |
| [antagonism of pozol and agrobacterium azotophilum on various species of bacteria and fungi, some of them pathogenic to man]. | | 1975 | 1059217 |
| [nitrogen fixation in monospecific and mixed cultures of aerobacter aerogenes and agrobacterium azotophilum using different sources of carbon]. | | 1975 | 1059219 |
| improvements of the membrane filter method for dna:rrna hybridization. | we describe and recommend the following improvements of dna:rrna membrane filter hybridization methods. one of our aims was to avoid dna release from filter discs during hybridization. 1. our hybridization conditions are 2 ssc in aq. dest., with 20% formamide, 50 c, overnight for 16 hr. 2. duplexing is over in 8-10 hr. 3. formamide has to be very pure (o.d. less than or equal to 0.2/cm light path at 270 nm). 4. rnaase treatment: 250 mug/5 ml 2 ssc/filter at 37 c for 1 hr. 5. our conditions for s ... | 1975 | 1082296 |
| 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 ... | 1976 | 1085123 |
| [immobilization of rhizobium lupini bacteroids in polyacrylamide gel]. | | 1975 | 1093828 |
| production of cellulose microfibrils by rhizobium. | electron microscope examination of rhizobium spp. revealed microfibrils produced by flocculating strains but not by nonflocculating strains. the microfibrils from r. trifolii (na30) were isolated and identified as cellulose by enzymatic, x-ray diffraction, and infrared spectral analyses. both infective and noninfective strains of r. trifolii flocculated and produced microfibrils. more infection threads were observed in clover root hairs growing in the presence of flocs in comparison with root ha ... | 1975 | 1096821 |
| crown gall tumors: are bacterial nucleic acids involved? | | 1975 | 1100042 |
| regulation and genetics of bacterial nitrogen fixation. | | 1975 | 1101806 |
| methods for growing nitrogen-fixing bacteria separated from plant cells. | | 1975 | 1104122 |
| 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. | 1975 | 1104767 |
| [rapid method of determining the capacity for symbiotic nitrogen fixation in growing plants under sterile and under natural conditions]. | | 1975 | 1107764 |
| 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 ... | 1975 | 1113080 |
| 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 ... | 1975 | 1113375 |
| variation in colony characteristics and symbiotic effectiveness of rhizobium. | | 1975 | 1116979 |
| influence of combined nitrogen on the symbiosis between single colony isolates of rhizobium cb756 and macrotyloma axillare. | | 1975 | 1116982 |
| [microbiologic dehydrogenation of microcrystalline delta4-3-ketosteroids]. | | 1975 | 1117085 |
| characterization of different plaque-forming and defective temperate phages in agrobacterium. | four agrobacterium tumefaciens temperate phages (pb2a, pb6(omega), pv-1(lv-1) and ps8), were shown to have the same genome size. moreover hybridization experiments by the heteroduplex method and electron microscopy showed a 100% homology between these four phage genomes. indications for lysogeny were found by direct means for the agrobacterum timefaciens strain 396, agrobacterium radiobacter strain 8149 and agrobacterium species 0362 and by the electron microscope negative staining technique fo ... | 1975 | 1123610 |
| attempts to detect agrobacterium tumefaciens and bacteriophage ps8 dna in crown gall tumors by dna-dna-filter hybridization. | a systematic study of the dna-dna-filter reaction is presented which measures its ability to detect small amounts of simple dna (bacterial or bacteriophage) in model mixtures of dna immobilized on filters. saturation curves show qualitatively that significant binding occurs when there is 10% agrobacterium tumefaciens dna on the filter but not 1%. ps8 bacteriophage dna is detectable at a level of 0.1%. true saturation is not attained in the bacterial dna reaction : radioactivity bound represents ... | 1975 | 1125316 |
| some unusual fatty acids of rhizobium. | a number of unusual fatty acids were identified after isolation from rhizobium. they include 11-methyl-octadec-11-enoic, 12-methoxy-11-methyl- and 11-methoxy-12-methyloctadecanoic, and 11-methoxy- and 13-methoxynonadecanoic acids. | 1975 | 1128167 |
| polarographic determination of 3-keto sugars-1. | | 1975 | 1128262 |
| protein turnover measured by 18-o exchange with h2-18o in non-growing cells of agrobacterium tumefaciens. | | 1975 | 1133576 |
| acquisition of tumour-inducing ability by non-oncogenic agrobacteria as a result of plasmid transfer. | | 1975 | 1134573 |
| physical evidence of a plasmid in rhizobium japonicum. | | 1975 | 1140246 |
| plasmid required for virulence of agrobacterium tumefaciens. | the irreversible loss of crown gall-inducing ability of agrobacterium tumefaciens strain c-58 during growth at 37 c is shown to be due to loss of a large plasmid (1.2 x 10-8 daltons). the gene responsible for this high rate of plasmid loss at elevated temperatures seems to be located on the plasmid. in addition, another spontaneous avirulent variant, a. tumefaciens strain iibnv6 is shown to lack the virulence plasmid which its virulent sibling strain, iibv7, possesses. deoxyribonucleic acid reas ... | 1975 | 1141196 |
| identification and grouping of bacteria by numerical analysis of their electrophoretic protein patterns. | improved methods for the identification and grouping of bacteria by polyacrylamide gel electrophoresis of soluble proteins are described. electrophoretic protein patterns were obtained in rigorously standardized comditions. the results were much more reproducible than any described previously. some of the factors affecting reproducibility were; growth conditions, time and speed of centrifugation of extracts, and conditions of gel electrophoresis. protein patterns were compared by computing corre ... | 1975 | 1141858 |
| identification of the rhizobium strains in pea root nodules using genetic markers. | pea plants were inoculated jointly with pairs of genetically marked strains of rhizobium leguminosarum. out of 297 modules examined 56 contained both inoculant strains. the ratios of the strains in the inoculum did not affect the frequencies of mixed nodules. generally one of the strains consistently occupied the majority of the nodules and ithe mixed nodules comprised the majority of bacteria. transfer of the p-group r factor, rp4, between certain strains of rhizobium within mixed nodules was d ... | 1975 | 1141859 |
| isolation and characterization of a rod-shaped bacteriocin from a strain of rhizobium. | a bactericidal agent ('bacteriocin 16-2') produced by rhizobial strain 16-2 had been characterized as a sheathless rod-shaped particle with a length of 200 nm and a diam. of 8 nm. one end of the rod is pointed and carries short fibre-like appendages, while the other end appears square. the particles specifically adsorb with their pointed end to bacteriocin-sensitive, but not to bacteriocin-resistant, cells. the possible mode of action of this bacteriocin in discussed. | 1975 | 1141864 |
| a genetic model for pathogenicity in agrobacterium and for tumour induction in plants. | | 1975 | 1142794 |
| plant genotype times rhizobium strain interactions in white clover. | | 1975 | 1147320 |
| studies on agrobacterium tumefaciens. iv. nonreplication of the bacterial dna in mung beam (phaseolus aureus). | | 1975 | 1147920 |
| [regulation of nitrogenase from lupin bacteroids]. | | 1975 | 1149612 |
| agrocin 84 sensitivity: a plasmid determined property in agrobacterium tumefaciens. | it was shown for some oncogenic agrobacterium tumefaciens strains that agrocin 84 sensitivity is determined by the presence of a large closed circular dna plasmid, called the ti-plasmid. whereas wild-type strain c58 is agrocin 84 sensitive, all ti-plasmid cured derivatives were found to be fully resistant. moreover all independently isolated agrocin 84 resistant colonies were stably non-oncogenic and plasmid negative. in a growth experiment carried out at 37 degrees c it was shown that the ki ... | 1975 | 1152843 |
| the occurrence of twitching motility among gram-negative bacteria. | almost 1000 strains representing well above 50 different species or groups of gram-negative bacteria were examined for twitching motility. this kind of motility was mainly found in strictly aerobic cocci and rods (viz. acinetobacter calcoaceticus, moraxella spp., neisseria gonorrhoeae, n. meningitidis, pseudomonas spp., phenon 3 of thornley that is closely related to acinetobacter, and marine, yellow-pigmented rods), but also in the facultative eikenella corrodens and in anaerobic strains presum ... | 1975 | 1155115 |
| electron microscopic characterization of rhizobium bacteriophage 16-6-12 and its isolated deoxyribonucleic acid. | bacteriophage 16-6-12 of rhizobium lupini has a long, non-contractile tail and a head which is hexagonal in outline. the tail is 140 nm in length, 11 nm in diameter, and carries a short term fiber. analysis of the tail structure by optical diffraction indicates that it is of the helical "stacked disc" type. after phenol-extraction from purified particles, the dna of phage 16-6-12 can circularize in vitro. no significant difference in contour length was observed between the linear (14.34 plus or ... | 1975 | 1156101 |
| growth dynamics of agrobacterium tumefaciens in chemostat cultures limited by carbon source and mineral nutrients. | agrobacterium tumefaciens was grown in a chemostat in a chemically-defined medium which hs alpha-methyl d-glucoside, magnesium, manganese, phosphate or urea as the growth-limiting nutrient. steady-state biomass concentrations were dependent on the specific growth rate of the organism when alpha-methyl d-glucoside, manganese or phosphate were growth-limiting nutrients. during magnesium-limited growth, large undamped oscillations in biomass concentration occurred. in all chemostat cultures a varia ... | 1975 | 1156102 |
| acetylene reduction by pure cultures of rhizobia. | acetylene reduction has been demonstrated in pure cultures of rhizobia. the requirements and conditions necessary for the activity in rhizobium sp. 32h1 are described. the most important factors are a low cell density and a very low oxygen concentration. | 1975 | 1158849 |
| interactions between azotobacter and "phosphobacteria" and their establishment in the rhizosphere as affected by soil fertility. | the effects on plant growth of "bacterial fertilizers" prepared from azotobacter spp. and phosphate-solubilizing bacteria ("phosphobacteria") have been the subject of much controversy. cases where no plant-growth stimulation occurred may often be accounted for by the failure to establish the bacterial inocula in the rhizosphere. three factors that may influence inocula establishment, i.e. soil fertility, manuring, and interactions between azotobacter and "phosphobacteria," were examined in pot e ... | 1975 | 1164695 |
| action of water in depressing acetylene reduction by detached nodules. | adverse effects of water on acetylene reduction by detached soybean root nodules could not be attributed to ethanol formation, but apparently were associated with nodule tissue damage caused by detachment. intact nodules were not affected by moisture. | 1975 | 1167777 |
| regulation of predation by prey density: the protozoan-rhizobium relationship. | tetramitus rostratus and strains of hartmanella, naegleria, and vahlkampfia consumed large numbers of rhizobium meliloti cells in a salt solution, but protozoan multiplication and the bacterial decline stopped when the prey density fell to about 10-6 to 10-7 cells/ml. at higher prey densities, the maximum numbers of hartmanella sp. and naegleria sp. were proportional to the quantity of r. meliloti initially provided to the amoebas. when supplemental rhizobia were supplied to hartmanella sp. or n ... | 1975 | 1168441 |
| structural similarity of the membrane envelopes of rhizobial bacteroids and the host plasma membrane as revealed by freeze-fracturing. | the freeze-fracture technique was used to study the host plasma membrane and the membrane envelope of bacteroids in rhizobial root nodules of three host-rhizobium combinations. in all three combinations studied, the membrane envelopes of bacteroids are structurally similar to their host plasma membrane. however, the membrane appears to be reversed, because the number and arrangement of particles in the outer fractured face (face a, concave) and in the inner fractured face (face b, convex) of the ... | 1975 | 1168633 |
| acetylene reduction by transfilter suspension cultures of rhizobium japonicum. | | 1975 | 1169944 |
| involvement of oxyleghaemoglobin and cytochrome p-450 in an efficient oxidative phosphorylation pathway which supports nitrogen fixation in rhizobium. | cellular atp level, atp/adp ratio and nitrogenase activity rise when oxyleghaemoglobin is added to respiring suspensions of rhizobium japonicum bacteroids from soybean root nodules. increased gaseous o2 tension is much less efficient than oxyleghaemoglobin in stimulation of bacteroid atp production. studies with the inhibitor carbonyl cyanide m-chlorophenylhydrazone show this atp to be generated as a consequence of oxidative phosphorylation. n-phenylimidazole, a specific cytochrome p-450 inhibit ... | 1975 | 1169973 |
| nitrogen fixation by free-living rhizobium in a defined liquid medium. | | 1975 | 1170865 |
| nitrate reductase from bacteroides of rhizobium japonicum: enzyme characteristics and possible interaction with nitrogen fixation. | the soluble nitrate reductase of rhizobium japonicum bacteroids has been purified and its properties compared to those of aerobically grown cells. the enzymes from both sources are similar with molecular weights of about 70 000 suggesting no close relationship with the molybdo-protein component of nitrogenase. nitrite, the product of nitrate reductase, strongly inhibited the nitrogenase activity from bacteroids, at concentrations less than 100 mum. thus, an interference in the rate of nitrogen f ... | 1975 | 1170894 |
| role of pectic and cellulolytic enzymes in the invasion of the soybean by rhizobium japonicum. | past workers have suggested pectic enzyme involvement in the invasion of legumes by rhizobium. however, no role for pectic acid, pectin, or methyl cellulose depolymerase enzymes in the invasion of r. japonicum was suggested by the current study. seedling inoculation with infective bacteria did not result in increased enzyme activity. rhizobium japonicum cell-free culture extracts and 3-indoleacetic acid did not affect the activation, induction, or binding of these enzymes. | 1975 | 1172457 |
| inhibition of protein synthesis by d-threo-chloramphenicol in the laboratory and nodule forms of rhizobium lupini. | protein synthesis by both laboratory-grown bacteria and isolated nodule bacteroids of rhizobium lupini (strain wu8) is inhibited by d-threo-chloramphenicol, the bacteroid form being the more sensitive to the antibiotic. a comparison between the two forms of the uptake of [14c]chloramphenicol showed that the bacteria always attained a lower intracellular chloramphenicol concentration. it is proposed that the sensitivity difference is due to a difference in membrane permeability between the two fo ... | 1975 | 1176963 |
| the genus agrobacterium and plant tumorigenesis. | | 1975 | 1180518 |
| fragmentation analysis of extracellular acid polysaccharides from seven rhizobium strains. part i. d-glucuronic acid-containing oligosaccharides. | the extracellular, bacterial polysaccharides from seven rhizobium strains have been submitted to partial hydrolysis with acid. several neutral oligosaccharides, some containing pyruvic acid, were isolated together with d-glucuronic acid-containing oligosaccharides. the polysaccharide from rh. meliloti did not contain glucuronic acid. for the other six strains, the following components were characterized: 4-o-(beta-d-glucopyranosyluronic acid)-d-glucuronic acid, 4-o-(beta-d-glucopyranosyluronic a ... | 1975 | 1182711 |
| frequency of infection and efficiency of transfection of rhizobium meliloti cells and spheroplasts. | competent cultures of rhizobium meliloti cells and spheroplasts obtained by various methods were infected with dna of phage 1a. the frequency of infection among the cells and spheroplasts was 2 x 10(-8)-5 x 10(-10). the efficiency of transfection calculated from the ratio of plaque forming units to infective dna molecule of phage 1a was 5 x 10(-8) to 10(-10). frequency of infection and efficiency of transfection among the competent cells were by one order of magnitude higher in the case of the s ... | 1975 | 1189991 |
| the ribosomal ribonucleic acid of agrobacterium tumefaciens. | the 23s rrna of agrobacterium tumefaciens contains at least two nicks which result in the formation of rna components with mol.wts. of 0.52 x 10(6) and 0.48 x 10(6). thus under the usual conditions of extraction and analysis, no 23s rrna was recovered from the bacterium. the experiments show that 23s rrna is synthesized as a continuous chain, in which one or two nicks are formed almost immediately near the ends of the molecule and an additional nick in the middle at a later time. | 1975 | 1191256 |
| structure and biosynthesis of the ribosomal ribonucleic acids from the oncogenic bacterium agrobacterium tumefaciens. | the rrna of the oncogenic bacterium agrobacterium tumefaciens was extracted by several methods and analysed by polyacrylamide-gel electrophoresis. the large rrna of this bacterium is degraded in vivo during the maturation of the ribosome. the influence of mg2+ and denaturation on degradation of 23s rna was studied. in pulse and chase experiments, we identified two precursors of the rrna with mol.wts. of 1.04 x 10(6) and 0.70 x 10(6). from studies of the structure of the large rrna, we propose th ... | 1975 | 1191257 |
| toxicity of sodium and chloride ions to rhizobium spp. in broth and peat culture. | | 1975 | 1194132 |
| loss of symbiotic capacity in commercially useful strains of rhizobium trifolii. | | 1975 | 1194136 |
| the effect of the ratio of magnesium: calcium on numbers of rhizobium in liquid medium. | | 1975 | 1194137 |
| on the question of integration of agrobacterium tumefaciens deoxyribonucleic acid by tomato plants. | treatment of tomato plants with agrobacterium tumefaciens causes subsequently administered [3h]thymidine to be preferentially incorporated into a satellite deoxyribonucleic acid (dna) whose buoyant density is between that of bacterial dna (rho = 1.718 g/cm3) and plant main band dna (rho = 1.692 g/cm3). satellite dna upon shearing or sonic treatment releases fragments of higher and lower buoyant density, as reported by earlier investigators. the satellite has no significant base sequence homology ... | 1975 | 1194235 |
| factors influencing the formation and stability of d-glucoside 3-dehydrogenase activity in cultures of agrobacterium tumefaciens. | d-glucoside 3-dehydrogenase specific activity in agrobacterium tumefaciens was maximal towards the end of the exponential growth phase of batch cultures; over 90% of the activity disappeared within the next 15 h. manganese ions, although essential for growth of the organism, strongly repressed d-glucoside 3-dehydrogenase synthesis in sucrose medium but had little effect when the carbon source was methyl alpha-d-glucoside. d-glucoside 3-dehydrogenase activity increased linearly with increasing sp ... | 1975 | 1194891 |
| effect on microorganisms of volatile compounds released from germinating seeds. | volatile compounds evolved from germinating seeds of slash pine, bean, cabbage, corn, cucumber, and pea were evaluated for their ability to support growth of microorganisms in liquid mineral salts media lacking a carbon source. growth of eight bacteria was measured turbidimetrically and of six fungi as dry weight of mycelium. volatiles caused increased growth of pseudomonas fluorescens, bacillus cereus, erwinia carotovora, agrobacterium tumefaciens, a. radiobacter, rhizobium japonicum, mucor muc ... | 1975 | 1201509 |
| exopolysaccharide depolymerases induced by rhizobium bacteriophages. | enzymes induced by two rhizobium trifolii bacteriophages caused depolymerization of exopolysaccharides from most r. trifolii and r. leguminosarum strains tested, but did not, in general, attack the exopolysaccharides of r. meliloti, the slow-growing rhizobia, or agrobacterium. ca2+ and (or) mg2+ were required for enzyme activity. in all strains tested, depolymerization of exopolysaccharide occurred when there was successful phage infection, but depolymerization also occurred with exopolysacchari ... | 1975 | 1201510 |