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Genome sequence of Azotobacter vinelandii, an obligate aerobe specialized to support diverse anaerobic metabolic processes.
The complete genome sequence of A. vinelandii DJ is reported, which identified the chromosomal locations of the genes coding for the three known oxygen-sensitive nitrogenases, as well as genes codes for other oxygen- sensitive enzymes, such as carbon monoxide dehydrogenase and formate dehydrogen enzyme. Expand
Bradyrhizobium paxllaeri sp. nov. and Bradyrhizobium icense sp. nov., nitrogen-fixing rhizobial symbionts of Lima bean (Phaseolus lunatus L.) in Peru.
Two novel species are proposed to accommodate the uncovered clades of Phaseolus lunatus bradyrhizobia, which share highly related but distinct nifH and nodC symbiosis genes. Expand
Bradyrhizobium valentinum sp. nov., isolated from effective nodules of Lupinus mariae-josephae, a lupine endemic of basic-lime soils in Eastern Spain.
Phylogenetic analysis of concatenated housekeeping genes, recA, atpD and glnII, suggested that L. mariae-josephae strains represent a new Bradyrhizobium species, closely related to B. retamae' Ro19(T), but divergent from those of strains that nodulate other lupine species. Expand
Genetic diversity of indigenous rhizobial symbionts of the Lupinus mariae-josephae endemism from alkaline-limed soils within its area of distribution in Eastern Spain.
The genomic diversity of a collection of 103 indigenous rhizobia isolates from Lupinus mariae-josephae (Lmj), a recently described Lupinus species endemic to alkaline-limed soils from a restrictedExpand
The twin‐arginine translocation (Tat) system is essential for Rhizobium–legume symbiosis
Comparisons of nodule structure and location of green fluorescent protein (GFP)‐tagged bacteria within nodules indicated that the symbiotic process was blocked in the tat mutant at a stage previous to bacteria release into cortical cells, indicating that the Tat pathway is also critical for proteins relevant to the initial stages of the symbiosis process. Expand
Diversity and Evolution of Hydrogenase Systems in Rhizobia
Hup sequences diverged from the rest of rhizobial sequences, which might indicate that those organisms have evolved independently and possibly have acquired the sequences by horizontal transfer from an unidentified source. Expand
In vitro synthesis of the iron-molybdenum cofactor of nitrogenase.
Properties of the partially purified dinitrogenase activated by FeMo-co synthesized in vitro were comparable to those of dinitrogensase from the wild-type organism; e.g., ratios of acetylene- to nitrogen-reduction activities, as well as those ofacetylene reduction activities to EPR spectrum peak height at g = 3.65, were very similar. Expand
Substrate reduction properties of dinitrogenase activated in vitro are dependent upon the presence of homocitrate or its analogues during iron-molybdenum cofactor synthesis.
The structural features of the homocitrate molecule absolutely required for the synthesis of a catalytically competent iron-molybdenum cofactor were determined to be the hydroxyl group, the 1- and 2-carboxyl groups, and the R configuration of the chiral center. Expand
Hydrogenase genes from Rhizobium leguminosarum bv. viciae are controlled by the nitrogen fixation regulatory protein nifA.
The data suggest that hupSp is structurally and functionally similar to nitrogen fixation promoters, which would ensure regulated synthesis of uptake hydrogenase in the most common H2-rich environment for rhizobia, the legume nodule. Expand
Molybdenum in nitrogenase.
The biochemical process described by nitrogen fixation is the reduction of N2 to NH3, which can then be used for the synthesis of amino acids, nucleic acids, and other essential nitrogenous compounds, which ranks with photosynthesis as a process of fundamental importance to all life on earth. Expand