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Showing 1 to 12 of 12 for “"A. vinelandii"”.
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Nitrogen Fixation By Azotobacter Species In Mixed Culture
… in the medium of pure cultures of Azotobacter vinelandii until levels become high enough to repress nitrogenase synthesis. A. vinelandii and A. chroococcum were grown in mixed culture with yeasts and bacterial soil isolates in a nitrogen free medium. It was theorized that the yeast or the soil …
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Controlled Expression and Functional Analysis of the Iron-Sulfur Cluster Biosynthetic Machinery in Azotobacter vinelandii
… controlled expression of genes in Azotobacter vinelandii by using genomic fusions to the sucrose catabolic regulon. This system was used for the functional analysis of the A. vinelandii isc genes, whose products are involved in the maturation of [Fe-S] proteins. For this analysis the scrX gene, …
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Characterization of an altered MoFe protein from a nifV- strain from Azotobacter vinelandii
… nifV. By deleting the nifV gene from Azotobacter vinelandii we were able to study the role of homocitrate in nitrogenase catalysis. A poly-histidine tail was incorporated into the C-termini of the a-subunit permitting isolation of the homocitrateless MoFe protein by using metal affinity …
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Genetic analysis of nifF and nifA and site-directed mutagenesis of nifE in Azotobacter vinelandii
… biosynthesis) genes from <i>Azotobacter vinelandii</i> were genetically analyzed. The nucleotide sequence of the nifF gene, which encodes a flavodoxin, was determined. Specific mutation strains indicated that in <i>A vinelandii</i> flavodoxin is not the unique physiological electron donor …
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Azotobacter vinelandii Nitrogenase: Effect of Amino-Acid Substitutions at the Alpha Gln-191 Residue of the MoFe Protein on Substrate Reduction and CO Inhibition
… in the Alpha-subunit of the MoFe protein of A. vinelandii nitrogenase was targeted for substitution because its side chain is involved in a hydrogen-bond network from one of the terminal carboxylates of the homocitrate component of FeMo cofactor through to the backbone NH of Alpha Gly-61, which …
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The pathway of electron transfer within the nitrogenase complex
… characterization of a hybrid Azotobacter vinelandii-Clostridium pasteurianum Fe protein indicate that the region of the A. vinelandii Fe protein defined by residues 59 through 67 is involved in Fe protein-MoFe protein interaction. The rationale for construction of this hybrid Fe protein …
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Isolation of in vivo intermediates in iron sulfur cluster biogenesis
… for general cellular use. In <i>Azotobacter vinelandii</i> the isc operon contains eight genes which are transcribed together as a single operon: <i>iscR iscS iscU iscA hscB hscA fdx iscX</i>. The two central <i>isc</i> players include IscS, a cysteine desulfurase, and IscU the proposed site …
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Bacterial transport and horizontal gene transfer in subsurface: multiple-scale experimental studies
… transformation with the model strain Azotobacter vinelandii. The systematic experimental approaches consisted of quartz crystal microbalance with dissipation (QCM-D) and Fourier transform infrared spectroscopy (FTIR) for measuring extracellular DNA adsorption and the conformation of the attached …
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Studies on the structure and function of various nif and nif- associated gene products encoded within the Azotobacter vinelandii nif gene cluster
… the MoFe protein of nitrogenase from Azotobacter vinelandii. A gene replacement strategy was developed for oligonucleotide-directed mutagenesis of these proteins and the resulting biological and biochemical effects of these changes were examined. Identification of structurally important regions in …
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Role of the MoFe Protein β-95-Cysteinyl Residue in Nitrogenase Catalysis in <i>Azotobacter vinelandii</i>
… were introduced at β-95-Cys in <i>Azotobacter vinelandii</I>nitrogenase through site-directed mutagenesis and gene replacement method. Some crude extracts from the mutants with substitutions at β-Cys contain typical FeMo cofactor EPR signal. The β-95<sup>Asp</sup> MoFe protein also has …
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Biosynthesis of the Nitrogenase FeMo-cofactor from Azotobacter vinelandii: Involvement of the NifEN complex, NifX and the Fe protein
… protein produced by a nifB-deletion mutant of A. vinelandii. Using the poly-histidine fusion approach, apo-MoFe protein was obtained in sufficient quantities for detailed catalytic, kinetic and spectroscopic analyses. This multidisciplinary approach confirmed that apo-MoFe protein contained intact …
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Azotobacter vinelandii Nitrogenase: Multiple Substrate-Reduction Sites and Effects of pH on Substrate Reduction and CO Inhibition
… J et al., 1997). Altered MoFe proteins of A. vinelandii nitrogenase, with the a278Thr, a278Cys, a278Ala and a278Leu substitutions, were used to study the interactions of H+, C2H2, N2 and CO with the enzyme. All strains, except the a278Leu mutant strain, were Nif+. From measurement of the Km …