Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| light microscopy observations of tetrazolium-reducing bacteria in the endorhizosphere of maize and other grasses in brazil. | roots of field-grown tropical maize, panicum maximum jacq. and digitaria decumbens stent., and of sorghum and wheat grown in monoxenic culture with the diazotroph spirillum lipoferum (syn. azospirillum spp.) were examined for tetrazolium-reducing bacteria following incubation of roots in a malate-phosphate buffer-2,3,5-triphenyltetrazolium chloride medium. bacteria were observed between and in cells of the cortex, in intercellular spaces between the cortex and endodermis, in xylem cells, and in ... | 1978 | 667740 |
| nitrate and nitrite reductase negative mutants of n2-fixing azospirillum spp. | chlorate resistant spontaneous mutants of azospirillum spp. (syn. spirillum lipoferum) were selected in oxygen limited, deep agar tubes with chlorate. among 20 mutants from a. brasilense and 13 from a. lipoferum all retained their functional nitrogenase and 11 from each species were nitrate reductase negative (nr-). most of the mutants were also nitrite reductase negative (nir-), only 3 remaining nir+. two mutants from nr+ nir+ parent strains lost only nir and became like the nr+ nir- parent str ... | 1978 | 697499 |
| effect of oxygen and nitrate on nitrogen fixation and denitrification by azospirillum brasilense grown in continuous culture. | azospirillum brasilense was grown continuously at various levels of dissolved oxygen (o2) in a nitrogen-free medium containing malates as the carbon source. steady-state cultures were established only at o2 concentrations less than 0.0150 atm (1 atm = 101.325 pa) and rates of acetylene reduction (n2 fixation) and efficiencies of n2 fixation were maximal between 0.0050-0.0075 atm dissolved o2. these cultures appeared to be o2- or n2-limited. there was no evidence of a respiratory protective mecha ... | 1978 | 743647 |
| a taxonomic study of the spirillum lipoferum group, with descriptions of a new genus, azospirillum gen. nov. and two species, azospirillum lipoferum (beijerinck) comb. nov. and azospirillum brasilense sp. nov. | sixty-one strains of the root-associated nitrogen fixer spirillum lipoferum exhibited a similar morphology in peptone--succinate salts medium: vibrioid cells having a diameter of 1.0 micrometer. when grown in broth the cells had a single polar flagellum, but when grown on agar at 30 degrees c lateral flagella of shorter wavelength were also formed. the dna base composition was 69--71 mol% guanine + cytosine when determined by thermal denaturation. dna homology experiments indicated the occurrenc ... | 1978 | 356945 |
| isolation of azospirullum from diverse geographic regions. | we have isolated azospirillum (spirullum lipoferum) from roots of grasses of several genera collected from a number of tropical and subtropical-temperate locations. pure cultures were obtained from a small percentage of samples; no higher percentage was secured from tropical than from other grasses. acetylene reduction and distinctive growth in n-free soft agar deeps were inadequate to identify this genus, although helpful in initial screening. fluorescent antibody tests with antiserum against c ... | 1979 | 476547 |
| selective infection of maize roots by streptomycin-resistant azospirillum lipoferum and other bacteria. | the percentage of low-level streptomycin-resistant (20 microgram/ml) bacteria in surface-sterilized or washed maize roots was more than a thousand times higher than that in soil populations. there was also a higher incidence of resistant bacteria in rhizosphere as compared with non-rhizosphere soil and bacteria isolated from maize roots were relatively tolerant to several other antibiotics. azospirillum lipoferum was predominant in surface-sterilized roots of field-grown maize and was low-level ... | 1979 | 540253 |
| plant growth substances produced by azospirillum brasilense and their effect on the growth of pearl millet (pennisetum americanum l.). | azospirillum brasilense, a nitrogen-fixing bacterium found in the rhizosphere of various grass species, was investigated to establish the effect on plant growth of growth substances produced by the bacteria. thin-layer chromatography, high-pressure liquid chromatography, and bioassay were used to separate and identify plant growth substances produced by the bacteria in liquid culture. indole acetic acid and indole lactic acid were produced by a. brasilense from tryptophan. indole acetic acid pro ... | 1979 | 16345372 |
| characterization of azospirillum isolated from nitrogen-fixing roots of harvested sorghum plants. | root segments of harvested sorghum plants had acetylene reduction activity ranging from 11 to 61 nmol of ethylene formed per h per g (dry weight). five strains of azospirillum brasilense sp. nov. were isolated from root segments. | 1979 | 16345484 |
| hydrogen metabolism of azospirillum brasilense in nitrogen-free medium. | production of h2 by azospirillum brasilense under n2-fixing conditions was studied in continuous and batch cultures. net h2 production was consistently observed only when the gas phase contained co. nitrogenase activity (c2h2 reduction) and h2 evolution (in the presence of 5% co) showed a similar response to o2 and were highest at 0.75% dissolved o2. uptake hydrogenase activity, ranging from 0.3 to 2.5 mumol h2/mg protein per hour was observed in batch cultures under n2. such rates were more tha ... | 1980 | 6257362 |
| an increase in nitrogen content of setaria italica and zea mays inoculated with azospirillum. | bacteria belonging to the genus azospirillum isolated from cynodon dactylon roots in israel were compared with azospirillum brasilense from brazil and california for their ability to fix nitrogen in association with grasses under greenhouse conditions. the plants were grown in a system which avoided cross inoculation from the inoculated soil to the control, while maintaining the natural soil microflora and humidity level in the soil close to field capacity. the organisms tested significantly inc ... | 1980 | 6769575 |
| characterization of a bacterium of the genus azospirillum from cellulolytic nitrogen-fixing mixed cultures. | a bacterium with the taxonomic characteristics of the genus azospirillum was isolated from celluloytic n2-fixing mixed cultures. its characteristics fit the descriptions of both azopirillum lipoferum (beijerinck) comb. nov. and azospirillum brasilense sp. nov. it may be a variant strain of a. lipoferum. in mixed cultures with cellulolytic organisms, the bacterium grew and fixed n2 with cellelose as a sole source of energy and carbon. the mixed cultures used cellulose from leaves of wheat (tritic ... | 1980 | 6773649 |
| transfer of plasmid prd1 from escherichia coli to azospirillum brasilense. | data are presented which indicate that plasmid prd1 can be transferred from escherichia coli to strains of azospirillum brasilense with a frequency of about 10(-7). the reverse was also possible; in this case the frequency of transfer appeared to be much higher, about 5 x 10(-1). transfer of the plasmid was also obtained between strains of a. brasilense; in this cross the transfer frequency was very high (about 10(-1)). moreover the prd1 plasmid seems very stable in a. brasilense cells. | 1980 | 6993864 |
| [chemotaxis of azospirillum lipoferum and azospirillum brasiliensis toward gramineae root exudates. i. corn, wheat and sorghum activity]. | 1980 | 7209175 | |
| [chemotaxis of azospirillum lipoferum and azospirillum brasiliensis. ii. activity of the amino acids contained in gramineae root exudates]. | 1980 | 7209176 | |
| dinitrogen-fixing bacteria: computer-assisted identification of soil isolates. | dinitrogen-fixing (acetylene-reducing) bacteria may be readily isolated from soils but extensive biochemical or immunobiological testing, or both, are required to identify them absolutely. a computer-assisted scheme for identification of nine genera of dinitrogen-fixing bacteria was developed and tested. the computer program is based on interpretation of the 70 biochemical tests of the api 20e and 50e, supplemented with tests for acetylene reduction, nitrate and nitrite reduction, catalase, oxid ... | 1980 | 7214218 |
| comparative studies of nitrogen-fixing bacteria associated with grasses in israel with azospirillum brasilense. | free-living, dinitrogen-fixing bacteria associated with roots of grasses were isolated from several locations in israel. bacteria with characteristics similar to those of azospirillum were isolated from cynodon dactylon roots and were compared with azospirillum brasilense from brasil (sp-7) and from california (cd). colonies of the israeli isolates were yellow and consisted of curved rods, 0.5-0.6 micron in diameter with polar flagella, whereas colonies of a. brasilense were pink (sp-7) and red ... | 1980 | 7397611 |
| association of azospirillum with grass roots. | the association between grass roots and azospirillum brasilense sp 7 was investigated by the fahraeus slide technique, using nitrogen-free medium. young inoculated roots of pearl millet and guinea grass produced more mucilaginous sheath (mucigel), root hairs, and lateral roots than did uninoculated sterile controls. the bacteria were found within the mucigel that accumulated on the root cap and along the root axes. adherent bacteria were associated with granular material on root hairs and fibril ... | 1980 | 16345490 |
| biology of azospirillum-sugarcane association: enhancement of nitrogenase activity. | azospirillum brasilense was reisolated from associations with callus tissue cultures of sugarcane and compared with stock cultures of the inoculated bacterium and related strains. although the reisolate had a growth rate similar to stock cultures, it exhibited a severalfold increase in maximum specific activity of nitrogenase. the reisolate and the parent culture had similar ultrastructure. the general ultrastructure of azospirillum is described. the bacterium was capsulated when grown on nitrog ... | 1980 | 16345531 |
| increase in dry weight and total nitrogen content in zea mays and setaria italica associated with nitrogen-fixing azospirillum spp. | the association between nitrogen-fixing bacteria from the genus azospirillum and the grasses zea mays and setaria italica was investigated in sterilized leonard-jar assemblies. nitrogen-fixing bacteria isolated from cynodon dactylon roots in israel and azospirillum brasilense (sp-7, sp-80, and cd) were examined. c(2)h(2) reduction activity was detected in systems containing 0.0 to 0.08 but not in those containing 0.16 gram per liter nh(4)no(3). the organisms tested significantly increased plant ... | 1980 | 16661514 |
| a single medium for the isolation of acetylene-reducing (dinitrogen-fixing) bacteria from soils. | a single medium, containing standard basal salts and three common carbon sources (sucrose, mannitol, and sodium lactate) is proposed to replace nitrogen-free media in common use for isolating dinitrogen-fixing bacteria. eight commonly isolated genera of dinitrogen-fixing bacterial exhibited growth on this combined carbon medium that equalled or bettered growth on other carbon-containing media. combined carbon medium also yielded the highest counts of putative dinitrogen-fixing bacteria from thre ... | 1981 | 7214234 |
| polygalacturonic acid transeliminase production by azospirillum species. | polygalacturonic acid transeliminase (pate) was produced by all of six azospirillum strains studied. characteristics were similar to those of pate from other bacteria: activity was maximal at ph 8.0 and was stimulated by cacl2. polygalacturonic acid was used more readily than pectin as a substrate. polygalacturonic acid in the medium stimulated pate production by several but not all strains. in all cases some of the pate produced in cultures remained bound to cell walls. in one strain, most rema ... | 1981 | 7237287 |
| physiological properties and plasmid content of several strains of azospirillum brasilense and a. lipoferum. | four strains of azospirillum brasilense, including strain 7000 (atcc 29145) and five strains of a. lipoferum, including strain br17 (atcc 29709) were examined for the presence of plasmids. all the strains were found to harbour 1 to 5 plasmids whose molecular weight ranged from 3.5 to over 300 md. no obvious relationship between the plasmids and phenotypic properties was established as yet, in particular n2 fixation, substrate utilization, drug resistance and lysogenic state. six out of the 9 str ... | 1981 | 6789740 |
| effect of inoculation of zea mays with azospirillum brasilense strains under temperate conditions. | seven strains of azospirillum brasilense were compared for their effect on the growth of zea mays grown under temperate conditions in sand--vermiculite pot cultures. inoculation with all seven strains tested, including fix(-) mutant strains, increased dry weight and total nitrogen content of shoots, but nitrogen concentrations were unaffected. low and variable rates of acetylene reduction activity were observed from excised roots of inoculated plants without preincubation. estimates of n2-fixing ... | 1981 | 6796245 |
| effects of temperature, nitrogen fertilization, and plant age on nitrogen fixation by setaria italica inoculated with azospirillum brasilense (strain cd). | the association between the nitrogen-fixing bacterium azospirillum brasilense (strain cd) and the grass setaria italica was studied under different environmental and soil conditions. highest acetylene reduction rates in intact plants were observed at the booting stage of setaria (2350 nmol ethylene produced hour(-1) plant(-1)) at 27 c. higher temperatures, up to 32 c, enhanced ethylene reduction. significant increases in shoot dry weight, panicle weight, and length were obtained in inoculated pl ... | 1981 | 16661913 |
| root-associated n(2) fixation (acetylene reduction) by enterobacteriaceae and azospirillum strains in cold-climate spodosols. | n(2) fixation by bacteria in associative symbiosis with washed roots of 13 poaceae and 8 other noncultivated plant species in finland was demonstrated by the acetylene reduction method. the roots most active in c(2)h(2) reduction were those of agrostis stolonifera, calamagrostis lanceolata, elytrigia repens, and phalaris arundinacea, which produced 538 to 1,510 nmol of c(2)h(4).g (dry weight). h when incubated at po(2) 0.04 with sucrose (ph 6.5), and 70 to 269 nmol of c(2)h(4). g (dry weight).h ... | 1981 | 16345687 |
| plant yield and nitrogen content of a digitgrass in response to azospirillum inoculation. | two australian soils, a vertisol (ph 6.8, 0.299% n) and a sandy yellow podzol (ph 6.2, 0.042% n), were used with digitgrass, digitaria sp. x46-2 (pi 421785), in a growth room experiment. comparisons were made between plants inoculated with live and autoclaved bacterial suspensions of australian and brazilian isolates of azospirillum brasilense. seedlings were inoculated on days 10 and 35. acetylene-reducing activity was measured five times during the experiment. dry matter yields of the digitgra ... | 1981 | 16345707 |
| l-arabinose metabolism in azospirillum brasiliense. | an oxidative pathway by which l-arabinose is converted to alpha-ketoglutarate in crude extracts of azospirillum brasiliense is demonstrated. specific activities of enzymes involved in the pathway were determined, and several pathway intermediates were identified. | 1982 | 6798025 |
| immunological techniques to identify azospirillum associated with wetland rice. | azospirilla associated with wetland rice were isolated and characterized by employing immunodiffusion and immunofluorescence techniques. antisera against two strains belonging to azospirillum lipoferum produced at least one heat-labile precipitation band with most isolates of a. lipoferum and a. brasilense. antisera against two strains belonging to a. lipoferum and one strain belonging to a. brasilense produced one band only with strains of their respective species. fluorescent antibody reaction ... | 1982 | 6809301 |
| enhancement of specific nitrogenase activity in azospirillum brasilense and klebsiella pneumoniae, inhibition in rhizobium japonicum under air by phenol. | specific nitrogenase activity in azospirillum brasilense atcc 29145 in surface cultures under air is enhanced from about 50 nmol c2h4 x mg protein -1 x h-1 to 400 nmol c2h4 by the addition of 1 mm phenol. 0.5 and 2 mm phenol added increase the rate 5-fold and 4-fold. this enhancement effect is observed only between 2 and 3 days after inoculation, with only a small reduction of the growth of the cells by the phenol added. in surface cultures under 1% o2, nitrogenase activity is slightly reduced b ... | 1982 | 6812526 |
| cloning of a nitrogen fixation (nif) gene cluster of azospirillum brasilense. | homology was detected between the structural genes for the nitrogenase complex of k. pneumoniae (nifhdk genes) and the total dna of several azospirillum strains. bacteriophage lambda gt 7-ara6 was used to construct a gene bank of a. brasilense strain 7000 dna and a recombinant phage carrying a 6.7 kb eco ri fragment, termed abri, was selected by hybridization with the k. pneumoniae nif probe. using heteroduplex analysis the extent of the homology of the abri fragment and the k. pneumoniae nif ge ... | 1982 | 6812651 |
| azospirillum: genetics, physiology, ecology. workshop, university of bayreuth, germany, july 16-17, 1981. | 1982 | 6953015 | |
| aerotactic response of azospirillum brasilense. | five strains of azospirillum brasilense and two of azospirillum spp., from israel, responded to self-created and preformed oxygen gradients by forming aerotactic bands in capillary tubes and actively moving toward a specific zone with low dissolved oxygen. increasing the oxygen concentration in capillaries containing phosphate buffer increased the number of attracted bacteria and decreased band velocity. high o2 concentrations and h2o2 temporarily repulsed the bacteria, causing the formation of ... | 1982 | 7130127 |
| a rapid immunofluorescence method for the study of the association of azospirillum sp. with maize roots. | 1982 | 6765358 | |
| characterization of a temperate bacteriophage for azospirillum. | 1982 | 6291236 | |
| improved medium for isolation of azospirillum spp. | colonies of azospirillum spp. could be readily distinguished from colonies of other diazotrophs by scarlet coloration in culture media in which congo red was included. | 1982 | 16346123 |
| plasmid visualization and nif gene location in nitrogen-fixing azospirillum strains. | a modified gel electrophoresis technique provided a reproducible way of detecting and isolating plasmids with molecular weights ranging from 12 x 10(6) to 370 x 10(6) for azospirillum species. analysis with the nifhd region of rhizobium trifolii showed that the azospirillum nif genes were chromosomally located in all eight strains investigated and not on endogenous plasmids. | 1983 | 6309750 |
| influence of pn2 and pd2 on hd formation by various nitrogenases. | formation of hd from d2 has been demonstrated with nitrogenase preparations from azotobacter vinelandii, clostridium pasteurianum, klebsiella pneumoniae, and azospirillum sp. we conclude that the formation of hd from d2 is a general property of nitrogenases. however, the nitrogenases differ in their ki values for d2 (n2 fixation) and in their rates of catalyzing hd formation; among the nitrogenases tested, c. pasteurianum nitrogenase had the lowest activity for formation of hd. when contaminatin ... | 1983 | 6354256 |
| metabolism of various carbon sources by azospirillum brasilense. | azospirillum brasilense sp7 and two mutants were examined for 19 carbon metabolism enzymes. the results indicate that this nitrogen fixer uses the entner-doudoroff pathway for gluconate dissimilation, lacks a catabolic but has an anabolic embden-meyerhof-parnas hexosephosphate pathway, has amphibolic triosephosphate enzymes, lacks a hexose monophosphate shunt, and has lactate dehydrogenase, malate dehydrogenase, and glycerokinase. the mutants are severely deficient in phosphoglycerate and pyruva ... | 1983 | 6417113 |
| uptake of methionine sulfoximine by some n2 fixing bacteria, and its effect on ammonium transport. | the n2 fixing bacteria klebsiella pneumoniae, azospirillum brasilense, rhodopseudomonas sphaeroides and rhodospirillum rubrum, but not azotobacter vinelandii accumulate the glutamine analogue methionine sulfoximine in the cell. in the accumulating cells methionine sulfoximine inhibits ammonium transport. accumulation and inhibition are prevented by glutamine. | 1983 | 6418571 |
| use of reducing compounds in the cultivation of azospirillum sp. | attempts were made to grow the micro-aerophilic n2-fixing bacterium azospirillum sp. in complete liquid medium by incorporating some reducing agents. ascorbic acid, glutathione and na-thioglycollate stimulated while methylene blue inhibited the growth and n2-ase activity. in complete liquid medium, na-thioglycollate and ascorbic acid increased the n2-ase activity with increasing concentration up to 800 micrograms/ml. with glutathione, growth of the bacterium was increased markedly but n2-ase act ... | 1983 | 6419535 |
| occurrence of azospirillum in polish soils. | n2-fixing azospirillum strains were isolated from garden soils and roots of wheat, rye, barley, oat and maize. the strains most active in c2h2 reduction were those isolated from garden soils, wheat and barley roots which produced 304 to 351 nmoles of c2h4 x h-1 per culture. the results demonstrate the presence of azospirillum in polish soils. | 1983 | 6198878 |
| the behaviour of azospirillum spp. in the presence of plant growth hormones. | tests were carried out to determine the effects of commercial preparations of indole-3-acetic acid (iaa), gibberellin (ga) and kinetin, separately and in combination, on azospirillum lipoferum and a. brasilense. these hormones showed no effect upon morphology, growth rate, or oxygen uptake. some random effects of ga, kinetin and the combination of hormones--but not of iaa alone--were observed on the number of viable cells. iaa, in the concentrations 0.001-1.0 microgram/ml, inhibited nitrogenase ... | 1983 | 6579879 |
| morphological and physiological characteristics and lipopolysaccharide composition of n2-fixing (c2h2-reducing) root-associated pseudomonas sp. | a dinitrogen-fixing pseudomonas sp. was isolated from the roots of the grass deschampsia caespitosa. the motile organism, which had 4 to 10 polar flagella, was gram negative, obligately aerobic, oxidase positive, arginine dihydrolase positive, and fluorescent. to verify api20b, api20e, and oxi-ferm identifications, as well as results from standard microbiological tests and electron microscopic examinations, which all indicated the organism to be a pseudomonas, we analyzed its lipopolysaccharide. ... | 1983 | 6652578 |
| nitrogenase activity (acetylene reduction) of root-associated, cold-climate azospirillum, enterobacter, klebsiella, and pseudomonas species during growth on various carbon sources and at various partial pressures of oxygen. | a comprehensive view of the diazotrophic bacterial flora of plants requires that attention be paid to the appropriate carbon and oxygen requirements during isolation of the bacteria. twenty compounds (monosaccharides, disaccharides, polyols, and organic acids) were therefore examined as carbon and energy sources for nitrogenase activity in semisolid stab cultures at po(2) values of 0.21, 0.02, and </=0.002 with 12 strains of diazotrophic root-associated bacteria. with the facultatively anaerobic ... | 1983 | 16346205 |
| enhanced mineral uptake by zea mays and sorghum bicolor roots inoculated with azospirillum brasilense. | inoculation of corn (zea mays) seeds with azospirillum brasilense strain cd or sp 7 significantly enhanced (30 to 50% over controls) the uptake of no(3), k, and h(2)po(4) into 3- to 4-day- and 2-week-old root segments. no gross changes in root morphology were observed; altered cell arrangement in the outer four or five layers of the cortex was seen in photomicrographs of cross sections of inoculated corn roots. the surface activity involved in ion uptake probably increased, as shown by the darke ... | 1983 | 16346311 |
| n(2) fixation by azospirillum brasilense and its incorporation into host setaria italica. | growth and nitrogen fixation were followed during the life cycle of setaria italica (foxtail millet) inoculated with azospirillum brasilense in controlled-environment growth chambers. the plants were fertilized at seeding with a limiting amount of combined nitrogen and maintained with an n-free mineral solution. during maturation of the plants, substantial nitrogenase activity, measured by acetylene reduction, developed in the rhizosphere, with total fixation estimated to be equivalent to 20% of ... | 1983 | 16346386 |
| uptake hydrogenase activity in denitrifying azospirillum brasilense grown anaerobically with nitrous oxide or nitrate. | zospirillum brasilense sp7 was grown anaerobically with n2o as the terminal electron acceptor and nh4cl as the nitrogen source. hydrogen uptake activity (o2-dependent h3h oxidation) was expressed in the presence and absence of 5% h2; it reached its maximum in late logarithmic phase as the malate became limiting. this activity was very stable in stationary phase, even in the absence of exogenous h2, compared with microaerobically grown cultures; this supports the hypothesis that the exclusion of ... | 1984 | 6690429 |
| fructose catabolism in azospirillum brasilense and azospirillum lipoferum. | the pathways for catabolism of fructose were investigated in the type strains of azospirillum lipoferum and azospirillum brasilense grown aerobically with (nh4)2so4 as the nitrogen source. when grown on fructose, the former species possessed a complete entner-doudoroff pathway, whereas the latter species lacked activity for glucose-6-phosphate dehydrogenase. both species possessed a complete catabolic embden-meyerhof-parnas pathway. neither species possessed the key enzyme of the hexose monophos ... | 1984 | 6735986 |
| catabolism of carbohydrates and organic acids and expression of nitrogenase by azospirilla. | fructose, galactose, l-arabinose, gluconate, and several organic acids support rapid growth and n2 fixation of azospirillum brasiliense atcc 29145 (strain sp7) as a sole source of carbon and energy. growth of azospirillum lipoferum atcc 29707 (strain sp59b) is also supported by glucose, mannose, mannitol, and alpha-ketoglutarate. oxidation of fructose and gluconate by a. brasiliense sp7 and of glucose, gluconate, and fructose by a. lipoferum sp59b was achieved through inducible enzymatic mechani ... | 1984 | 6588050 |
| intermediary carbon metabolism of azospirillum brasilense. | azospirillum brasilense sp 7 grew rapidly in azo medium containing reduced nitrogen and succinate as an energy source, with a doubling time of 43 min. no growth was measured with glucose as the sole carbon source. in contrast, azospirillum lipoferum sp 59b could grow in media containing either succinate or glucose with a doubling time of 69 min and 223 min, respectively. warburg-barcroft respirometry showed that the rate of oxygen consumption by a. brasilense sp 7 on glucose medium (0.034 mumol ... | 1984 | 6425263 |
| degradation of carbofuran by azospirillum lipoferum and streptomyces spp. isolated from flooded alluvial soil. | 1984 | 6498360 | |
| identification of a phosphoenolpyruvate:fructose 1-phosphotransferase system in azospirillum brasilense. | an inducible phosphoenolpyruvate:fructose phosphotransferase system has been detected in azospirillum brasilense, which requires a minimum of two components of the crude extracts for activity: (i) a soluble fraction (enzyme i) and (ii) a membrane fraction (enzyme ii). the uninduced cells neither show any uptake of fructose nor express activity of either of these two enzyme fractions. c-1 of fructose is the site of phosphorylation. this phosphotransferase system does not accept glucose as a subst ... | 1984 | 6501230 |
| hydrogenase activity in azospirillum brasilense is inhibited by nitrite, nitric oxide, carbon monoxide, and acetylene. | nitrite, no, co, and c2h2 inhibited o2-dependent h2 uptake (h3h oxidation) in denitrifying azospirillum brasilense sp7 grown anaerobically on n2o or no3-. the apparent ki values for inhibition of o2-dependent h2 uptake were 20 microm for no2-, 0.4 microm for no, 28 microm for co, and 88 microm for c2h2. these inhibitors also affected methylene blue-dependent h2 uptake, presumably by acting directly on the hydrogenase. nitrite and no inhibited h2 uptake irreversibly, whereas inhibition due to co ... | 1984 | 6384189 |
| [differentiation among species of the genus azospirillum]. | to replace the spirillum lipoferum denomination (2) for the nitrogen fixing group of soil spirilla, the azospirillum genus has been created in recent years (12), which includes two species: a. lipoferum and a. brasilense. both of them are nitrogen fixing bacteria able to induce a specific infection of grass roots (1, 6). consequently it is important to differentiate correctly the species when plant-bacteria relationships must be studied or inoculation assays must be carried out. for this reason ... | 1984 | 6400721 |
| [isolation of atmospheric-nitrogen-fixing spirilla from the waters of the paraná delta and other rivers]. | seventeen strains of spirillum-like organisms (2) were isolated from the parana delta and other rivers (table 1), using the following medium: 0.5% malic acid; 0.4% koh; 0.5% k2hpo4; 0.005% yeast extract; ph was adjusted to 7 with koh and 0.15% agar. the organisms produced a white, dense and sub-superficial pellicle in this medium, and streaking them on plates, single colonies could be isolated. they were easily recognized thanks to the congo red added to the medium, because the bacteria, as it h ... | 1984 | 6400725 |
| application of the indirect immunoperoxidase stain technique to the flagella of azospirillum brasilense. | an indirect immunoperoxidase stain was used to demonstrate by electron microscopy that an antigenic difference exists between the polar flagellum and the lateral flagella of azospirillum brasilense atcc 29145. | 1984 | 16346482 |
| responses of sorghum and pennisetum species to the n(2)-fixing bacterium azospirillum brasilense. | three field inoculation experiments, two in florida and one in new mexico, were conducted with azospirillum brasilense cd. each of the florida experiments evaluated two crop species. one species in each of the florida experiments responded to inoculation with a significant dry matter yield increases of 11 to 24% and nitrogen yield increases of 9 to 39%. no inoculation response was noted in the new mexico experiment. the responding species were sorghum bicolor (l.) moench (sorghum) and the inters ... | 1984 | 16346571 |
| isolation and characterization of dinitrogen-fixing bacteria from the rhizosphere of temperate cereals and forage grasses. | n(2)(c(2)h(2))-fixing bacteria were isolated from the rhizosphere of various cereals and forage grasses grown in the greenhouse and from the rhizosphere of field-grown wheat in sweden. all 46 isolates from the greenhouse plants lost their nitrogenase activity during purification. by imposing a stronger selection pressure, we obtained pure isolates with nitrogenase activity from field-grown wheat. some isolates were identified as enterobacter agglomerans and bacillus polymyxa, but several bacteri ... | 1984 | 16346635 |
| root hair deformation, bacterial attachment, and plant growth in wheat-azospirillum associations. | seven azospirillum strains induced more deformation of root hairs of wheat than did strains of rhizobium leguminosarum, azotobacter chroococcum, or escherichia coli. azospirillum sp. strain sp245 caused the most deformation. strain sp245 (isolated from surface sterile roots of wheat) and strain sp7 (isolated from the rhizosphere of a forage grass) were compared with regard to their effects on root hair deformation, their attachment to roots, and their effects on the growth of four wheat cultivar ... | 1984 | 16346680 |
| the phylogeny of purple bacteria: the alpha subdivision. | the technique of oligonucleotide cataloging shows the purple photosynthetic eubacteria to comprise three major subdivisions, temporarily called alpha, beta, and gamma--previously designated groups i-iii by gibson et al. (1979). each subdivision contains a number of non-photosynthetic genera in addition to the photosynthetic ones. the alpha subdivision, the subject of the present report, contains most but not all of the species that fall into the classically defined genera rhodospirillum, rhodo ... | 1984 | 11541974 |
| purification and properties of the nitrogenase of azospirillum amazonense. | the nitrogenase of the free-living, microaerobic, n2-fixing bacterium azospirillum amazonense (strain y1) was purified by chromatography on deae-52 cellulose, by heat treatment, and by preparative polyacrylamide gel electrophoresis. the specific nitrogenase activities were 2,400 nmol of c2h4 formed per min per mg of protein for dinitrogenase (mofe protein) and 1,800 nmol of c2h4 formed per min per mg of protein for dinitrogenase reductase (fe protein). the mofe protein was composed of a minimum ... | 1985 | 3864779 |
| [survival of azospirillum in the rhizosphere of festuca arundinacea]. | in two experiments festuca seeds (4 or 20 seeds/pot in first or second experiment respectively) were inoculated with azospirillum strains (sp 7, mutant streptomycin resistant and g strain) in controlled laboratory conditions. two illumination regimes were employed (197 and 274 microe. m-2.s-1, respectively). sp 7 cell number was determined during both experiments. the total number of diazotrophic bacteria was also determined on different dates. in both experiments the control pots received the s ... | 1985 | 3870740 |
| strain-specific chemotaxis of azospirillum spp. | chemotactic responses of three azospirillum strains originating from different host plants were compared to examine the possible role of chemotaxis in the adaptation of these bacteria to their respective hosts. the chemotaxis to several sugars, amino acids, and organic acids was determined qualitatively by an agar plate assay and quantitatively by a channeled-chamber technique. high chemotactic ratios, up to 40, were obtained with the latter technique. the chemotactic response did not rely upon ... | 1985 | 3884588 |
| flocculation in azospirillum brasilense and azospirillum lipoferum: exopolysaccharides and cyst formation. | the phenomena of flocculation and floc formation by azospirillum brasilense sp7 (atcc 29145) and azospirillum lipoferum sp59b (atcc 29707) were studied in aerobic liquid cultures. carbon sources representative of various entry pathways in combination with various nitrogen sources induced flocculation in both species of azospirilla. noticeably, the combination of fructose and nitrate was the most effective in terms of floc yields. phase-contrast microscopic observations revealed a transition in c ... | 1985 | 3894333 |
| salt tolerance of azospirillum brasilense. | the effect of various salts on the growth and n2-ase activity of azospirillum brasilense was tested. bicarbonate was found to be the most toxic, followed by chlorides and sulphate. tolerance of a. brasilense to these salts was comparable to that of many species of rhizobium. so4-- was stimulatory to growth and n2-ase activity up to 40 meq. the process of n2-fixation (n2-ase activity) was found to be more sensitive to all the salts tested as compared to growth. | 1985 | 3936328 |
| [plasmids of azospirillum brasilense]. | the cells from natural isolates of a. brasilense were found to harbour 1 to 4 plasmids with the molecular masses within the 27-300 md range. 100 md plasmids are specific for this bacterial species. strains isolated from the roots of cereals (wheat, maize, barley) have more heterogeneous plasmid composition as compared to the strains isolated from soil. | 1985 | 3939568 |
| purification and characterization of glutamate synthase from azospirillum brasilense. | growth conditions for azospirillum brasilense sp6 were devised for maximal expression of glutamate synthase. the enzyme levels were largely affected by the type and concentration of the nitrogen source. a 10-fold increase in the synthesis of the enzyme was observed at a limiting concentration of ammonia. the enzyme was purified to homogeneity by a procedure which was fairly rapid and allowed a good recovery of enzyme (30%). azospirillum glutamate synthase is a complex iron-sulfur flavoprotein wi ... | 1985 | 4019412 |
| heterologous hybridization of bacterial dna to the endoglucanases a and b structural genes cela and celb of clostridium thermocellum. | dna from various cellulolytic and non-cellulolytic bacteria was found to hybridize to clostridium thermocellum ncib10682 dna fragments carrying the structural genes cela and celb which code for endoglucanases a and b. homology to cela was detected in agrobacterium rhizogenes, azospirillum brasilense, bacillus subtilis, cellulomonas sp., clostridium stercorarium, erwinia chrysanthemi, pseudomonas solanacearum and streptomyces griseus. homology to celb was detected only in b. subtilis, c. stercora ... | 1985 | 4083831 |
| restriction endonucleases in azospirillum. | azospirillum brasilense, a. amazonense, and a. lipoferum strains were screened for restriction endonucleases using phage lambda dna. the extract of a. brasilense 29711 cleaved lambda dna into specific fragments. it was concluded that this strain possesses a class ii restriction endonuclease which was named abri. abri has a single recognition site on lambda dna at position of approx. 33 500 bp. abri was characterized as an isoschizomer of xhoi, which cuts lambda dna at 33 498 bp and cleaves doubl ... | 1985 | 3000892 |
| straw and xylan utilization by pure cultures of nitrogen-fixing azospirillum spp. | azospirillum spp. were shown to utilize both straw and xylan, a major component of straw, for growth with an adequate combined n supply and also under n-limiting conditions. for most strains examined, a semisolid agar medium was satisfactory, but several strains appeared to be capable of slow metabolism of the agar. subsequently, experiments were done with acid-washed sand supplemented with various carbon sources. in these experiments, authenticated laboratory strains, and all 16 recent field is ... | 1985 | 16346730 |
| influence of azospirillum strains on the nodulation of clovers by rhizobium strains. | mixed cultures of several azospirillum and rhizobium trifolii strains caused either an inhibition or stimulation of nodule formation on plant hosts as compared with nodulation of plants inoculated with r. trifolii alone. azospirillum strains affected the nodulation process at a precise cell ratio (r. trifolii/azospirillum cells) and time of inoculation. all azospirillum strains used showed a variation in their ability to inhibit or enhance nodulation by r. trifolii strains. when nonviable cell p ... | 1985 | 16346772 |
| interaction of azospirillum and rhizobium strains leading to inhibition of nodulation. | rhizobium-azospirillum interactions during establishment of rhizobium-clover symbiosis were studied. when mixed cultures of azospirillum and rhizobium trifolii strains were simultaneously inoculated onto clover plants, no nodulation by r. trifolii was observed. r. trifolii anu1030, which nodulated clover plants without attacking root hairs, i.e., does not cause root hair curling (hac), did not show inhibition of nodulation when inoculated together with azospirillum strains. isolation of bacteria ... | 1985 | 16346773 |
| carbohydrate catabolism in azospirillum amazonense. | the nitrogen fixer azospirillum amazonense grew on the various disaccharides, hexoses, and pentoses tested in this study but not on polyols and on some tricarboxylic acid cycle intermediates. an active transport system was detected for sucrose and glucose but not for mannitol and 2-ketoglutarate. six a. amazonense strains were examined for 16 carbon-metabolizing enzymes, and the results indicate that these strains employ the entner-doudoroff pathway to catabolize sucrose, fructose, and glucose. ... | 1985 | 16346836 |
| cellulose decomposition and associated nitrogen fixation by mixed cultures of cellulomonas gelida and azospirillum species or bacillus macerans. | mixed cultures of cellulomonas gelida plus azospirillum lipoferum or azospirillum brasilense and c. gelida plus bacillus macerans were shown to degrade cellulose and straw and to utilize the energy-yielding products to fix atmospheric nitrogen. this cooperative process was followed over 30 days in sand-based cultures in which the breakdown of 20% of the cellulose and 28 to 30% of the straw resulted in the fixation of 12 to 14.6 mg of n per g of cellulose and 17 to 19 mg of n per g of g straw con ... | 1985 | 16346898 |
| regulation of nitrogenase activity by ammonium chloride in azospirillum spp. | ammonium chloride (greater than or equal to 0.05 mm) effectively and reversibly inhibited the nitrogenase activity of azospirillum brasilense, azospirillum lipoferum and azospirillum amazonense. the glutamine synthetase inhibitor l-methionine-dl- sulfoximine abolished this "switch-off" in a. lipoferum and a. brasilense, but not in a. amazonense. azaserine, an inhibitor of glutamate synthase, inhibited nitrogenase activity itself. this provides further evidence for glutamine as a metabolite of re ... | 1986 | 3081492 |
| regulatory mutation that controls nif expression and histidine transport in azospirillum brasilense. | mutagenesis of azospirillum brasilense with nitrosoguanidine and selection on ethylenediamine yielded prototrophs which fixed nitrogen in the presence of ammonia. nitrogenase activity in mutant strains exceeded that of the wild type three- to sixfold. the same mutants were also constitutive for histidine transport. enzyme activities involved in ammonia assimilation were not affected by the mutation. the data suggest that the mutation occurred at a site which regulates nif and histidine transport ... | 1986 | 3087965 |
| nucleotide sequence of the azospirillum brasilense sp7 glutamine synthetase structural gene. | the complete nucleotide sequence of the glna gene, encoding the glutamine synthetase subunit of azospirillum brasilense sp7, was established. this is the first azospirillum gene sequenced. the gene encodes a 468 residue polypeptide of mw 51,917. the similarity coefficient (sab) between the polypeptidic sequence of azospirillum and anabaena 7120, which is the only other glna sequence available, is 58%. no significant homology with e. coli canonical and ntr promoters, or with the promoter region o ... | 1986 | 2878685 |
| cloning and characterization of the glna gene of azospirillum brasilense sp7. | a plasmid which, by complementation, restored a gln+nif+ phenotype to the gln-nif- azospirillum brasilense mutant 7029, was isolated from a gene bank of total dna of a. brasilense sp7 (atcc 29145) constructed in the broad host range vector pvk100. this plasmid contained the structural gene (glna) for glutamine synthetase. the glna gene was mapped by tn5 insertion and dna hybridization with a klebsiella pneumoniae glna probe. the direction of transcription of glna was determined. the glna product ... | 1986 | 2893582 |
| [plasmid content in strains of azospirillum sp]. | in this work, the plasmid content of 22 strains of a. brasilense and 7 of a. lipoferum, isolated from different regions of argentina was analyzed. of the several methods for the extraction of plasmids, a modification of that of kado and liu was found to be the most appropriate for the isolation of a larger number of high molecular weight plasmids. out of 29 strains analyzed, 26 were found to contain between one and four plasmids, all of them of high molecular weight (figure 3, table 1); 44% of t ... | 1986 | 3685390 |
| nadph/nadh-dependent cold-labile glutamate dehydrogenase in azospirillum brasilense. purification and properties. | a cold-labile glutamate dehydrogenase (gdh, ec 1.4.1.3) has been purified to homogeneity from the crude extracts of azospirillum brasilense. the purified enzyme shows a dual coenzyme specificity, and both the nadph and nadh-dependent activities are equally cold-sensitive. the enzyme is highly specific for the substrates 2-oxoglutarate and glutamate. kinetic studies with gdh indicate that the enzyme is primarily designed to catalyse the reductive amination of 2-oxoglutarate. the nadp+-linked acti ... | 1986 | 3956501 |
| nitrogen fixation associated with development and localization of mixed populations of cellulomonas sp. and azospirillum brasilense grown on cellulose or wheat straw. | mixed cultures of cellulomonas sp. and azospirillum brasilense were grown with straw or cellulose as the carbon source under conditions favoring the fixation of atmospheric nitrogen. rapid increases in cell numbers, up to 10 cells per g of substrate, were evident after 4 and 5 days of incubation at 30 degrees c for cellulose and straw, respectively. nitrogen fixation (detected by acetylene reduction measured on parallel cultures) commenced after 2 and 4 days of incubation for straw and cellulose ... | 1986 | 16347042 |
| comparison of two cellulomonas strains and their interaction with azospirillum brasilense in degradation of wheat straw and associated nitrogen fixation. | a mutant strain of cellulomonas sp. cs1-17 was compared with cellulomonas gelida 2480 as the cellulolytic component of a mixed culture which was responsible for the breakdown of wheat straw to support asymbiotic nitrogen fixation by azospirillum brasilense sp7 (atcc 29145). cellulomonas sp. strain csi-17 was more efficient than was c. gelida in cellulose breakdown at lower oxygen concentrations and, in mixed culture with a. brasilense, it supported higher nitrogenase activity (c(2)h(2) reduction ... | 1986 | 16347043 |
| enhancement of wheat root colonization and plant development by azospirillum brasilense cd. following temporary depression of rhizosphere microflora. | inoculation of wheat with azospirillum brasilense, combined with the application of four fungal and bacterium-inhibiting substances to which a. brasilense is resistant in the soil, decreased the rhizosphere population, while it increased wheat root colonization by a. brasilense, even in cases of poor inoculation. the inoculation significantly increased the following wheat plant parameters as well: plant dry weight, number of tillers per plant, spikelet fertility, harvest index, and grain yield. ... | 1986 | 16347052 |
| close association of azospirillum and diazotrophic rods with different root zones of kallar grass. | the populations of diazotrophic and nondiazotrophic bacteria were estimated in the endorhizosphere and on the rhizoplane of kallar grass (leptochloa fusca) and in nonrhizosphere soil. microaerophilic diazotrophs were counted by the most-probable-number method, using two semisolid malate media, one of them adapted to the saline-sodic kallar grass soil. plate counts of aerobic heterotrophic bacteria were done on nutrient agar. the dominating n(2)-fixing bacteria were differentiated by morphologica ... | 1986 | 16347149 |
| [resistance to antibiotics in strains of azospirillum sp]. | a total of 32 strains of azospirillum mainly isolated from rhizosphere of grasses and soils of argentina were examined for susceptibility to 9 antimicrobial agents (trimethoprim, ampicillin, carbenicillin, streptomycin, spectinomycin, chloramphenicol, kanamycin, nalidixic acid and tetracycline). many of the strains were sensitive to tetracycline, kanamycin, chloramphenicol and nalidixic acid, and resistant to ampicillin (more than 50 mg/l) and carbenicillin (more than 200 mg/l). in spite of this ... | 1987 | 3685393 |
| regulation of nitrogenase activity by oxygen in azospirillum brasilense and azospirillum lipoferum. | the nitrogenase activity of the microaerophilic bacteria azospirillum brasilense and a. lipoferum was completely inhibited by 2.0 kpa of oxygen (approximately 0.02 atm of o2) in equilibrium with the solution. the activity could be partially recovered at optimal oxygen concentrations of 0.2 kpa. in contrast to the nh4+ switch off, no covalent modification of the nitrogenase reductase (fe protein) was involved, as demonstrated by western-blotting and 32p-labeling experiments. however, the inhibiti ... | 1987 | 2880836 |
| assimilation of 13nh4+ by azospirillum brasilense grown under nitrogen limitation and excess. | the specific activities of glutamine synthetase (gs) and glutamate synthase (gogat) were 4.2- and 2.2-fold higher, respectively, in cells of azospirillum brasilense grown with n2 than with 43 mm nh4+ as the source of nitrogen. conversely, the specific activity of glutamate dehydrogenase (gdh) was 2.7-fold higher in 43 mm nh4+-grown cells than in n2-grown cells. these results indicate that nh4+ could be assimilated and that glutamate could be formed by either the gs-gogat or gdh pathway or both, ... | 1987 | 2887545 |
| construction of a gene library from azospirillum brasilense and characterization of a recombinant containing the nif structural genes. | 1. we have constructed a gene library, from azospirillum brasilense using the vector embl4. 2. a recombinant containing the nif structural genes from a. brasilense was isolated and characterized. this recombinant contains a dna insert of about 15 kilobases (kb) which gives rise to five fragments after cleavage with ecori. only one of the dna fragments (6.5 kb) hybridized to the nifhdk genes of klebsiella pneumoniae. 3. the organization of the nif genes in this dna fragment was determined using d ... | 1987 | 2837298 |
| cyst production and brown pigment formation in aging cultures of azospirillum brasilense atcc 29145. | encystation in azospirillum brasilense atcc 29145 was observed by using routine laboratory staining and phase-contrast and electron microscopy. encystment occurred in liquid and in solid or semisolid media containing fructose (8 mm) and kno3 (0.5 mm). the encysted forms consisted of a central body filled with poly-beta-hydroxybutyric acid granules, an electron-transparent intinelike region, and a thick outer layer. enlarged giant encysted forms with multiple central bodies were also observed dur ... | 1987 | 3104311 |
| [effect of pesticides on bacterial membranes]. | the effect of pure preparation of ordram, fosalon, ddt, methoxychlorine, hydrel, dihydrel, 2,4-d, 2m-4c and of technical preparations of saturn, linuron, ronstar and keltan on the membrane functions (respiration and motility) of azospirillum brasilense and chromatium minutissimum cells and on malate and nadh oxidation by the isolated membranes of micrococcus lysodeikticus was investigated. the effect varied from irreversible impairment to undetectable impairment of the measured activities depend ... | 1987 | 3112764 |
| regulation of fructose uptake and catabolism by succinate in azospirillum brasilense. | fructose uptake and catabolism in azospirillum brasilense is dependent on three fructose-inducible enzymes (fru-enzymes): (i) enzyme i and (ii) enzyme ii of the phosphoenolpyruvate:fructose phosphotransferase system and (iii) 1-phosphofructokinase. in minimal medium containing 3.7 mm succinate and 22 mm fructose as sources of carbon, growth of a. brasilense was diauxic, succinate being utilized in the first phase of growth and fructose in the second phase with a lag period between the two growth ... | 1987 | 2957360 |
| a highly sensitive bacterial assay for toxins based on swarming inhibition, and comparison with the cup plate assay based on growth inhibition. | the motility inhibition of the swarming bacteria proteus mirabilis and azospirillum brasilense was found to be an appropriate parameter to indicate toxic effects caused by some mycotoxins, lactones and anhydrides of dicarboxylic acids. if these substances are in contact with the motile bacteria the following phenomena can be observed: at a certain toxin concentration the swarming of the bacteria is inhibited. if the concentration is increased the swarming ceases, and at still higher concentratio ... | 1987 | 3299877 |
| [characteristics of dissociation in cultures of aspergillus brasilense sp7]. | peculiarities of dissociation in the cultures of nitrogen-fixating soil microorganism azospirillum brasilense have been studied. the possible transfer among colony-morphology variants is established. the relations between variants are described by the following scheme: r in equilibrium with sr----s electrophoretic analysis of plasmid contents in different variants of azospirillum brasilense supposes the possible participation of plasmid dna in the dissociation process in this microorganism. | 1987 | 3683426 |
| root-zone-specific oxygen tolerance of azospirillum spp. and diazotrophic rods closely associated with kallar grass. | the effect of oxygen on n(2)-dependent growth of two azospirillum strains and two diazotrophic rods closely associated with roots of kallar grass (leptochloa fusca) was studied. to enable precise comparison, bacteria were grown in dissolved-oxygen-controlled batch and continuous cultures. steady states were obtained from about 1 to 30 mum o(2), some of them being carbon limited. all strains needed a minimum amount of oxygen for n(2)-dependent growth. nitrogen contents between 10 and 13% of cell ... | 1987 | 16347257 |
| close association of azospirillum and diazotrophic rods with different root zones of kallar grass. | [this corrects the article on p. 522 in vol. 52.]. | 1987 | 16347260 |
| enzyme-linked immunosorbent assay for specific identification and enumeration of azospirillum brasilense cd. in cereal roots. | the enzyme-linked immunosorbent assay is suggested as a reliable, sensitive, and highly specific method for the identification and enumeration of azospirillum brasilense cd. as few as 10 cfu/ml can be practically identified by this method. at higher bacterial numbers, sensitivity increased linearly up to 5 x 10 cfu/ml, yielding useful standard curves. no cross-reaction was found either with different closely related azospirillum strains or with other rhizosphere bacteria. the method allows for a ... | 1987 | 16347284 |
| transposon mutagenesis of azospirillum brasilense and azospirillum lipoferum: physical analysis of tn5 and tn5-mob insertion mutants. | tn5-induced insertion mutants were generated in azospirillum brasilense sp7 and a. lipoferum spbr17 by mating with escherichia coli strains carrying suicide plasmid vectors. the sources of tn5 were the suicide plasmids pgs9 and psup2021. kanamycin-resistant azospirillum colonies appeared from crosses with e. coli at maximum frequencies of 10 per recipient cell. transposon tn5 also conferred streptomycin resistance on azospirillum colonies as was observed earlier for rhizobium sp. eight tn5-induc ... | 1987 | 16347289 |
| plant cell wall carbohydrates as substrates for azospirillum brasiliense. | carbohydrate components (simple sugars and polysaccharides) of cell walls of pearl millet (pennisetum americanum l., cv. gahi) were studied as potential substrates for the root-associated diazotroph azospirillum brasiliense sp. 7. simple sugars were utilized, but no evidence was obtained to support the suggestion that the polysaccharide components tested might serve as substrates for growth following hydrolysis by the associated azospirilla. | 1987 | 16347490 |
| isolation and characterization of azospirillum brasilense loci that correct rhizobium meliloti exob and exoc mutations. | the occurrence in azospirillum brasilense of genes that code for exopolysaccharide (eps) synthesis was investigated through complementation studies of rhizobium meliloti exo- mutants. these mutants are deficient in the synthesis of the major acidic eps of rhizobium species and form empty, non-nitrogen-fixing root nodules on alfalfa (j. a. leigh, e. r. signer, and g. c. walker, proc. natl. acad. sci. usa 82:6231-6235, 1985). we demonstrated that the exoc mutation of r. meliloti could be corrected ... | 1988 | 3182731 |
| [response of maize to inoculation with azospirillum brasilense]. | 1988 | 3244926 |