Improvement of common bean (Phaseolus vulgaris) nodulation by selected rhizobial strain from Egyptian soils through genotypic characterization, symbiotic effectiveness and competitiveness under salt stress conditions

To maximize the symbiotic nitrogen fixation of common bean (Phaseolus vulgaris) under egyptian soil conditions, twelve rhizobial isolates were isolated from root nodulated common bean. These isolates were physiologiacl characterized to test the more effeicient strains in nitrogen fixation, to select strains more adapted to environmetal stresses such as salinity, alkalinity, temperature. The adapted strains were selected to study the competitiveness of these strains against the standard strain CIAT 899 marked with gus gene under normal conditions, stress of salinity and stress of alkalinity. These strains were also characterized using molecular biology techniques such as REP-PCR, ARDRA of 16S and 23S rDNA, plasmid profiles analysis, sequencing of full length of 16S rDNA, hybridization with nifH gene and amplification of nodC gene. Strain EBRI 26 and Sinorhizobium meliloti strain 2010 were selected as salt tolerant strains to study the proteins involeved in salt tolerance by 2D proteom analysis and MALDI-Tof mass spectrometry

How to manage a scientific project in biological nitrogen fixation (BNF) and the topics that needed to be searched?

Abstract Planning to have a good scientific project generally or specifically in BNF is a main target for young scientists and PhD students worldwide. Therefore, it is hardly urgent to well manage the project, which defined the use of knowledge, skills and methods to achieve objectives of the project in the determined time without delay. Consequently, in this letter I will explain the main points that needed to be covered to manage a research project in BNF and which subjects of research are requested to be covered in the future

The promiscuity of Phaseolus vulgaris L. (common bean) for nodulation with rhizobia: a review

12 páginas, 1 figura, 1 tablaPhaseolus vulgaris L. (common bean) is a legume indigenous to American countries currently cultivated in all continents, which is nodulated by diferent rhizobial species and symbiovars. Most of species able to nodulate this legume worldwide belong to the genus Rhizobium, followed by those belonging to the genera Ensifer (formerly Sinorhizobium) and Pararhizo bium (formerly Rhizobium) and minority by species of the genus Bradyrhizobium. All these genera belong to the phylum alpha-Proteobacteria, but the nodulation of P. vulgaris has also been reported for some species belonging to Paraburkholderia and Cupriavidus from the beta-Proteobacteria. Several species nodulating P. vulgaris were originally isolated from nodules of this legume in American countries and are linked to the symbiovars phaseoli and tropici, which are currently present in other continents probably because they were spread in their soils together with the P. vulgaris seeds. In addition, this legume can be nodulated by species and symbiovars originally isolated from nodules of other legumes due its high promiscuity, a concept currently related with the ability of a legume to be nodulated by several symbiovars rather than by several species. In this article we review the species and symbiovars able to nodulate P. vulgaris in diferent countries and continents and the challenges on the study of the P. vulgaris endosymbionts diversity in those countries where they have not been studied yet, that will allow to select highly efective rhizobial strains in order to guarantee the success of P. vulgaris inoculationThis review article was funded under the fnancial project STDF1268 from the Academy of Scientifc Research and Technology Applications, Cairo, Egypt. Special thanks should be given by authors to the reviewers who gave important notes that contributed signifcantly to strength our manuscript.Peer reviewe

Arsenate bioremediation by <i>Bacillus pumilus </i> through <i> cis-</i> acting of both arB and subtilisin genes

518-524Accumulation of arsenate in the natural environment causes serious environmental problems. Hence, the main goal of the present study was to isolate arsenic-resistant bacteria capable of removing arsenic from the environment. Screening of 30 bacterial isolates, isolated from arsenate-contaminated soil, revealed a highly resistant strain, which could tolerate up to 2g L-1 of arsenate. This strain was identified as Bacillus pumilus based on the partial sequences of 16S rRNA. Molecular tools, such as, differential display-PCR, cloning and sequencing were used to screen and identify genes that can be involved in arsenate bioremoval. Differential display for scanning the most abundant of induced/suppressed genes at different sodium arsenate concentrations of the bacterial genome indicated the significant induction of the two genes, arsenical pump membrane protein (arB) and subtilisin. It was noticed that the arB gene was up regulated at high arsenate concentrations, while subtilisin gene was induced at low concentrations. The results showed that arB gene and subtilisin were working together for reducing the arsenate effect through its hydrolysis by β-galactosidase enzyme. The study gives significant insight about the expected mechanism of both two genes for remediating arsenate-polluted ecosystems

Draft Genome Sequences of Four Novel Thermal- and Alkaline-Tolerant EgyptianRhizobiumStrains Nodulating Berseem Clover

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Table_1_Exploring the antibacterial potential of plant extracts and essential oils against Bacillus thermophilus in beet sugar for enhanced sucrose retention: a comparative assessment and implications.pdf

Sugar beet is one of the greatest sources for producing sugar worldwide. However, a group of bacteria grows on beets during the storage process, leading to a reduction in sucrose yield. Our study focused on identifying common bacterial species that grow on beets during manufacturing and contribute to sucrose loss. The ultimate goal was to find a potential antibacterial agent from various plant extracts and oils to inhibit the growth of these harmful bacteria and reduce sucrose losses. The screening of bacterial species that grow on beet revealed that a large group of mesophilic bacteria, such as Bacillus subtilis, Leuconostoc mesenteroides, Pseudomonas fluorescens, Escherichia coli, Acinetobacter baumannii, Staphylococcus xylosus, Enterobacter amnigenus, and Aeromonas species, in addition to a dominant thermophilic species called Bacillus thermophilus, were found to be present during the manufacturing of beets. The application of 20 plant extracts and 13 different oils indicated that the extracts of Geranium gruinum, Datura stramonium, and Mentha spicata were the best antibacterials to reduce the growth of B. thermophilus with inhibition zones equal to 40, 39, and 35 mm, respectively. In contrast, the best active oils for inhibiting the growth of B. thermophilus were Mentha spicata and Ocimum bacilicum, with an inhibitory effect of 50 and 45 mm, respectively. RAPD-PCR with different primers indicated that treating sugar juice with the most effective oils against bacteria resulted in new recombinant microorganisms, confirming their roles as strong antibacterial products. The characterization of Mentha spicata and Ocimum bacilicum oils using GC/MS analysis identified cis-iso pulegone and hexadecanoic acid as the two main bioactive compounds with potential antibacterial activity. An analysis of five genes using DD-PCR that have been affected due to antibacterial activity from the highly effective oil from Mentha spicata concluded that all belonged to the family of protein defense. Our findings indicate that the application of these pure antibacterial plant extracts and oils would minimize the reduction of sucrose during sugar production.</p