abstract soil beneficial microorganisms such as plant growth promoting rhizobacteria (pgpr) are able to enhance plant growth. the research was conducted using a randomized complete block design as split plot factorial with three factors (nutrient management, azospirillum and azotobacter strains) .in this experiment the effect of azospirillum and azotobacter inoculation on yield and yield compon...

Detection of viable Azotobacter in soils stored in the laboratory for more than 10 years suggests that these bacteria can remain dormant in nature for prolonged periods of time. Studies of dried cultures show that cysts of A. vinelandii 12837 remain viable for at least 10 years, whereas vegetative cells do not survive for even 1 year under the same conditions.

in order to study the effect of different n fertilizer on berseem forage in an intercropping with basil, this experiment was conducted in research farm of college of agriculture, university of tehran during growing season 2011. experimental treatments were arranged as split plots based on a randomized complete block design with three replications. different fertilizers consisted of control (no ...

Protein turnover occurs during differentiation of Azotobacter vinelandii 12837 to the extent of 50% during encystment and 7% during germination. The addition of rifampin at the initiation of encystment prevents encystment and inhibits turnover. In germinating cysts, protein turnover is essential owing to an apparent lack of certain amino acid biosynthetic enzymes. The capacity to synthesize sul...

The temperature characteristic of respiration of Azotobacter vinelandii possesses a constant value of 19,330 +/- 165 over the temperature range 20-30 degrees C. This value is independent of pH, oxygen tension, age of culture, and other factors within the limits studied. The optimum temperature of respiration is 34-35 degrees C., with limits at about 10 degrees and 50 degrees C.

Two Azotobacter vinelandii strains capable of growing on N2(Nif+) were isolated from two different mutant strains that lacked dinitrogenase activity (Nif-). Extracts of N2-grown cells of the two Nif+ strains lacked significant amounts of the "conventional" dinitrogenase protein subunits, as determined by two-dimensional gel electrophoresis. Instead, the extracts contained at least four new prot...

We sequenced the nitrogen fixation regulatory gene nfrX from Azotobacter vinelandii, mutations in which cause a Nif- phenotype, and found that it encodes a 105-kDa protein (NfrX), the N terminus of which is highly homologous to that of the uridylyltransferase-uridylyl-removing enzyme encoded by glnD in Escherichia coli. In vivo complementation experiments demonstrate that the glnD and nfrX prod...

A mixture of five saturated 5-n-alkylresorcinol homologues was isolated from vegetative cells of the nitrogen-fixing soil bacterium Azotobacter chroococcum Az12. Their structures were established by spectrometry (1H NMR, EI-MS, FAB-MS, FAB-MS/MS) and chromatography (GC, TLC) means.