Search results for "sinorhizobium"
showing 3 items of 13 documents
Polymer-induced phase separation in suspensions of bacteria
2010
We study phase separation in suspensions of two unrelated species of rod-like bacteria, Escherichia coli and Sinorhizobium meliloti, induced by the addition of two different anionic polyelectrolytes, sodium polystyrene sulfonate or succinoglycan, the former being synthetic and the latter of natural origin. Comparison with the known behaviour of synthetic colloid-polymer mixtures and with simulations show that "depletion" (or, equivalently, "macromolecular crowding") is the dominant mechanism: exclusion of the non-adsorbing polymer from the region between two neighbouring bacteria creates an unbalanced osmotic force pushing them together. The implications of our results for understanding phe…
Studio sulla relazione tra la resistenza alla kanamicina ed il gene “Putative aminoglycoside 3’-phosphotranferase (PAPH) in Sinorhizobium meliloti ce…
2008
Il ceppo selvatico di Sinorhizobium meliloti 1021 è sensibile alla kanamicina (30 mg/l) anche se Capela et al. (Proc. Natl. Acad. Sci. U.S.A.(2001), 98: 9877-9882), analizzando l’intero genoma, hanno trovato un gene codificante per una “putative aminoglycoside 3'-phosphotransferase” (PAPH), coinvolta nella resistenza ad antibiotici aminoglicosidici quali la kanamicina. Un mutante spontaneo (GM42) kanamicina resistente (200 mg/l) di Sinorhizobium meliloti 1021 è stato caratterizzato da un punto di vista molecolare e fenotipico per analizzare l’attività del gene PAPH. Il ceppo parentale e GM42 sono stati caratterizzati da un punto di vista microbiologico tramite il MicroLog System Biolog. I r…
Different species and symbiotic genotypes of field rhizobia can nodulate Phaseolus vulgaris in Tunisian soils.
2002
Abstract A collection of 160 isolates of rhizobia nodulating Phaseolus vulgaris in three geographical regions in Tunisia was characterized by restriction fragment length polymorphism analysis of polymerase chain reaction (PCR)-amplified 16S rDNA, nifH and nodC genes. Nine groups of rhizobia were delineated: Rhizobium gallicum biovar (bv.) gallicum, Rhizobium leguminosarum bv. phaseoli and bv. viciae, Rhizobium etli bv. phaseoli, Rhizobium giardinii bv. giardinii, and four groups related to species of the genus Sinorhizobium, Sinorhizobium meliloti, Sinorhizobium medicae and Sinorhizobium fredii. The most abundant rhizobial species were R. gallicum, R. etli, and R. leguminosarum encompassing…