The high-potential 4Fe-4S* center ofAzotobacter vinelandii ferredoxin I has been titrated potentiometrically by a reductive procedure. The absorbance decrease at 510 nm accompanying the reduction of the high-potential center titrated with an Em of 320 mV (n = 1). The low-potential 4Fe-4S* center was titrated by using the absorbance decrease at 410 nm to monitor its reduction. This center exhibi...

Plant growth-promoting bacteria –PGPB– are microorganisms that can grow in, on, or around plant tissues and stimulate plant growth by numerous mechanisms (Vessey 2003). Within this group, nitrogen-fixing bacteria play a remarkable role in plant nutritition. They can take N2 from atmosphere and make it available for plant uptake (Halbleib and Ludden 2000). Azotobacter, a nitrogen-fixing bacteria...

The enzyme which cleaves the benzene ring of 6-chlorohydroxyquinol was purified to apparent homogeneity from an extract of 2,4,6-trichlorophenol-grown cells of Streptomyces rochei 303. Like the analogous enzyme from Azotobacter sp. strain GP1, it exhibited a highly restricted substrate specificity and was able to cleave only 6-chlorohydroxyquinol and hydroxyquinol and not catechol, chlorinated ...

CooA is a heme-containing transcriptional activator that enables Rhodospirillum rubrum to sense and grow on CO as a sole energy source. We have identified a number of CooA homologs through database searches, expressed these heterologously in Escherichia coli, and monitored their ability to respond to CO in vivo. Further in vitro analysis of two CooA homologs from Azotobacter vinelandii and Carb...

Cyclopropane fatty acids constitute 25% of the phospholipid acyl groups in cysts of Azotobacter vinelandii. These are lost by dilution during germination when the synthesis of the fatty acids characteristic of vegetative cell phospholipids commences.

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Azotobacter synthesizes an extensive internal membranous nework when grown with air (N(2)), i.e., under conditions when these bacteria fix nitrogen. Very slight quantities of internal membrane, concentrated mainly about the cell periphery, are formed when Azotobacter grows with fixed nitrogen, i.e., ammonia and amino acids. Compared to cells growing with ammonia, cells utilizing atmospheric nit...

The present investigation “The effect of biofertilizers on growth, yield and quality Cape Gooseberry (Physalis peruviana L.) in Prayagraj agroclimatic conditions” was undertaken at Central Research Field, Department Horticulture, Naini Agricultural Institute, Sam Higginbottom University Agriculture, Technology & Sciences, (UP) during 2022-2023. main objective the experiment to find out vari...

Strains of aerobic, microaerobic, nonsymbiotic, and symbiotic dinitrogen-fixing bacteria were screened for the presence of alternative nitrogenase (N2ase) genes by DNA hybridization between genomic DNA and DNA encoding structural genes for components 1 of three different enzymes. A nifDK gene probe was used as a control to test for the presence of the commonly occurring Mo-Fe N2ase, a vnfDGK ge...

Temperature affects the expression of the three different nitrogenases in Azotobacter vinelandii. Molybdenum repressed the vnfH and anfH operons relatively more at 30 degrees C than at 20 degrees C; at 14 degrees C molybdenum did not repress these genes at all. Similarly, V repressed the anf operon at 30 degrees C but not at 20 or 14 degrees C. Mo was poorly transported into cells grown at the ...