Acetylene Reduction Analysis
Mostrando 1-12 de 21 artigos, teses e dissertações.
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1. Taxonomia de pracriontes isolados de cnidários de São Sebastião, SP, Brasil / Taxonomy of prokaryontes isolated from cnidarians of São Sebastião, SP, Brasil
Microorganisms have a key role in the health of cnidarians establishing ecologic relationships, of parasitism to mutualism. The knowledge on the diversity of prokaryotes associated with corals in Brazil is very limited. This is the first study on the taxonomic characterization of heterotrophic bacteria, including putative N2-fixing and specially vibrios isol
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/04/2010
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2. Cyanobacteria in mangrove ecosystems: isolation, morphology and genetic diversity / Cianobactérias em ecossistemas de manguezais: isolamento, morfologia e diversidade genética
Manguezais são ecossistemas de transição entre ambientes terrestres e marinhos encontrados em regiões tropicais e subtropicais. A ampla faixa de variações de salinidade e teor oxigênio, típica desses ambientes, está entre os principais fatores condicionantes da colonização e desenvolvimento da biota. Apesar disso, são ambientes com elevada produ�
Publicado em: 2010
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3. Non-Frankia Actinomycetes Isolated from Surface-Sterilized Roots of Casuarina equisetifolia Fix Nitrogen†
Based on partial 16S sequences, we previously described a novel group of nonsymbiotic, acetylene reduction activity-positive actinomycetes which were isolated from surface-sterilized roots of Casuarina equisetifolia growing in Mexico. An amplified rRNA restriction analysis confirmed that these actinomycetes are distinct from Frankia, a finding substantiated
American Society for Microbiology.
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4. Analysis of the Symbiotic Performance of Bradyrhizobium japonicum USDA 110 and Its Derivative I-110 and Discovery of a New Mannitol-Utilizing, Nitrogen-Fixing USDA 110 Derivative †
Previously, Bradyrhizobium japonicum USDA 110 was shown to contain colony morphology variants which differed in nitrogen-fixing ability. Mannitol-utilizing derivatives L1-110 and L2-110 have been shown to be devoid of symbiotic nitrogen fixation ability, and non-mannitol-utilizing derivatives I-110 and S-110 have been shown to be efficient at nitrogen fixati
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5. Hydroponic Growth and the Nondestructive Assay for Dinitrogen Fixation 1
Hydroponic growth medium must be well buffered if it is to support sustained plant growth. Although 1.0 millimolar phosphate is commonly used as a buffer for hydroponic growth media, at that concentration it is generally toxic to a soybean plant that derives its nitrogen solely from dinitrogen fixation. On the other hand, we show that 1.0 to 2.0 millimolar 2
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6. Comparing Denitrification Estimates for a Texas Estuary by Using Acetylene Inhibition and Membrane Inlet Mass Spectrometry
Characterizing denitrification rates in aquatic ecosystems is essential to understanding how systems may respond to increased nutrient loading. Thus, it is important to ensure the precision and accuracy of the methods employed for measuring denitrification rates. The acetylene (C2H2) inhibition method is a simple technique for estimating denitrification. How
American Society for Microbiology.
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7. Nitrogen-fixing nodules induced by Agrobacterium tumefaciens harboring Rhizobium phaseoli plasmids.
Rhizobium phaseoli CFN299 forms nitrogen-fixing nodules in Phaseolus vulgaris (bean) and in Leucaena esculenta. It has three plasmids of 185, 225, and 410 kilobases. The 410-kilobase plasmid contains the nitrogenase structural genes. We have transferred these plasmids to the plasmid-free strain Agrobacterium tumefaciens GMI9023. Transconjugants containing di
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8. Evidence for NH4+ switch-off regulation of nitrogenase activity by bacteria in salt marsh sediments and roots of the grass Spartina alterniflora.
The regulatory effect of NH4+ on nitrogen fixation in a Spartina alterniflora salt marsh was examined. Acetylene reduction activity (ARA) measured in situ was only partially inhibited by NH4+ in both the light and dark after 2 h. In vitro analysis of bulk sediment divided into sediment particles, live and dead roots, and rhizomes showed that microbes associa
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9. Tight coupling of root-associated nitrogen fixation and plant photosynthesis in the salt marsh grass Spartina alterniflora and carbon dioxide enhancement of nitrogenase activity.
The coupling of root-associated nitrogen fixation and plant photosynthesis was examined in the salt marsh grass Spartina alterniflora. In both field experiments and hydroponic assay chambers, nitrogen fixation associated with the roots was rapidly enhanced by stimulating plant photosynthesis. A kinetic analysis of acetylene reduction activity (ARA) showed th
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10. Symbiotic Deficiencies Associated with a coxWXYZ Mutant of Bradyrhizobium japonicum
The terminal oxidase complexes encoded by coxMNOP and coxWXYZ were studied by analysis of mutations in each of the two oxidases. Carbon monoxide difference spectra obtained from membranes of coxMNOP mutant bacteroids were like those obtained for the wild type, whereas bacteroid membranes of a coxWXYZ mutant were deficient in CO-reactive cytochrome b. Experim
American Society for Microbiology.
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11. Novel Endophytic Nitrogen-Fixing Clostridia from the Grass Miscanthus sinensis as Revealed by Terminal Restriction Fragment Length Polymorphism Analysis
Anaerobic nitrogen-fixing consortia consisting of N2-fixing clostridia and diverse nondiazotrophic bacteria were previously isolated from various gramineous plants (K. Minamisawa, K. Nishioka, T. Miyaki, B. Ye, T. Miyamoto, M. You, A. Saito, M. Saito, W. Barraquio, N. Teaumroong, T. Sein, and T. Tadashi, Appl. Environ. Microbiol. 70:3096-3102, 2004). For thi
American Society for Microbiology.
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12. Role of a Ferredoxin Gene Cotranscribed with the nifHDK Operon in N2 Fixation and Nitrogenase “Switch-Off” of Azoarcus sp. Strain BH72
The endophytic diazotroph Azoarcus sp. strain BH72 is capable of infecting rice roots and of expressing the nitrogenase (nif) genes there. In order to study the genetic background for nitrogen fixation in strain BH72, the structural genes of nitrogenase (nifHDK) were cloned and sequenced. The sequence analysis revealed an unusual gene organization: downstrea
American Society for Microbiology.