Efficacy of liquid formulation of versatile rhizobacteria isolated from soils of the North-Western Himalayas on <i>Solanum lycopersicum</i>

660-668In the present study, a total of 53 indigenous diazotrophs and phosphate solubilizing bacteria (PSB) were isolated from the rhizosphere soils of five different crops grown in Palampur, (Himachal Pradesh, India). Out of these, isolates WT-A1 and WT-A2 exhibited significantly higher nitrogenase activity as compared to the reference strain Azotobacter chroococum and PT-P2 solubilized more phosphate as compared to the reference strain Pseudomonas striata. WT-A2 and PT-P2 showed multiple plant growth promoting traits including indole acetic acid, ammonia and siderophore production. On the basis of morphological, biochemical and 16S rRNA gene sequence analysis, WT-A2 and PT-P2 were identified as Stenotrophomonas sp. and Burkholderia cepacia, respectively. The liquid formulation of efficient diazotroph and PSB was prepared in sterilized liquid manure, matka khaad with the addition of trehalose which maintained their viable counts for one year. Evaluation of growth performance of liquid formulation on Solanum lycopersicum (Avtar 7711) in vivo concluded that seed bacterization (SB) and seed bacterization, seedling dipping, soil application and foliar spray (SB+SD+SA+FS) exhibited better results in terms of seed germination, fruit quality, dehydrogenase activity and available nitrogen, phosphorus and potassium of soil as compared to the other treatments

Potential applications of blue green algae

13-20Blue green algae (BGA) possess immense morphological and metabolic diversity and can be used in economic developmentand environment management like wastewater treatment, land reclamation, production of fine chemicals, atmospheric fixation ofnitrogen, production of methane fuel, conversion of solar energy, therapeutic functions and so on. This review presents applicationsof BGA in agriculture, food and industry

Protocol optimization for RAPD in cyanobacteria

549-552Random amplification of polymorphic DNA (RAPD) analysis using the polymerase chain reaction proved a useful technique in the biodiversity analysis of microorganisms but may lack reproducibility in the poorly standardized methodology. In the present investigation, the RAPD technique was optimized for characterizing cyanobacterial isolates in order to ensure its reproducibility and discriminatory power. Cyanobacterial isolates from the three genera, Anabaena, Nostoc and Calothrix were examined for the fragment patterns produced using different 10-mer RAPD primers and concentrations of different components (DNA template, primer and Taq polymerase) at two different annealing temperatures. It was observed that variations associated with all the parameters tested modified the fingerprinting pattern. For conditions not optimized, RAPD bands were faint and difficult to score. Therefore, a set of conditions for RAPD-PCR reaction has been defined, to ensure simple and fast reproducibility

Lipid production and molecular dynamics simulation for regulation of accD gene in cyanobacteria under different N and P regimes

Abstract Background Microalgae grown under different nutrient deficient conditions present a good source of natural lipids with applications for several types of biofuels. The expression of acetyl-CoA carboxylase gene can further provide an insight to the mechanisms leading to enhanced lipid production under such stresses. In this study, two nutrients viz. nitrogen and phosphorus were modulated to see its effect on lipid productivity in selected cyanobacteria and its correlation with Accase followed by molecular dynamics simulation. Results Selected cyanobacteria viz. Oscillatoria sp. (SP8), Anabaena sp. (SP12), Anabaena sp. (SP13), Microcoleus sp. (SP18), and Nostoc sp. (SP20) varied in their ability to accumulate lipids which ranged from a lowest of 0.13% in Anabaena sp. (SP13) to the maximum of 7.24% in Microcoleus sp. (SP18). Microcoleus sp. (SP18) also recorded highest lipid accumulation at both N (6 mM NaNO3) and P (0.20 mM K2HPO4) limiting conditions. The overall expression of accD was found to be upregulated in both Oscillatoria sp. (SP8) and Microcoleus sp. (SP18) for all nitrogen concentrations but was differentially regulated with both positive and negative induction under phosphorus stress conditions. Maximum induction was observed in Microcoleus sp. (SP18) at 0.20 mM K2HPO4. The obtained 3D structure of SP8 protein (21.8 kDa) showed six alpha helices, while SP18 protein (16.7 kDa) exhibited four alpha helices and four beta sheets. The phi (ϕ)/psi(ψ) angles of the amino acid residues observed in Ramachandran plot analysis showed that both SP8 and SP18 proteins were highly stable with more than 90% amino acids in allowed regions. The molecular dynamics simulation results also indicated the stability of ligand-bound protein complexes. Conclusion It has been demonstrated that cyanobacterial isolates are affected differently by nutrient limitation leading to variation in their lipid productivity. The same has been revealed by the behavior of accD gene expression which was regulated more by nutrients concentrations rather than the organism. However, the ligand-bound protein complexes were stable throughout MD simulations