The grouping of A. glycyphyllos nodulators into one, obviously separate monophyletic cluster, PHA-793887close to the symbiovar biserrulae mesorhizobia and jointly with other Mesorhizobium species, demonstrated in the nodC gene phylogram, was consistent with that offered in the nodA gene tree. Hence, equally of these genes, of rhizobia certain for A. glycyphyllos nodulators, show up to share a frequent genealogy and possibly derive from a single ancestor. It is highly possible that evolution of the host and alterations in the hosts environment have exerted selection strain on liquorice milkvetch symbionts and shaped the framework of the bacterial nod genes. It is also well worth emphasizing, that nodC and nodA alleles of symbiovar biserrulae rhizobia break up off at a basal situation of the liquorice milkvetch symbionts, which correlates with the shut relationship of these microorganisms host vegetation i.e. Biserrula pelecinus and A. glycyphyllos belonging to the identical subtribe Astragalinae. To replicate the genetically dependent symbiosis adaptive phenotype , shown by liquorice milkvetch nodulators, we suggest the new symbiovar glycyphyllae for bacteria forming nitrogen-repairing associations with A. glycyphyllos. The nodC gene, encoding a chitin synthase and relevant to host specificity, is typically utilized for symbiovar determination in rhizobia. Presently, inside the genus Mesorhizobum three subsequent symbiovars are described, i.e.: biserrulae , loti and ciceri . These symbiovars are evidently distinguished on the basis of nodC gene sequences and they illustrate the effectively adaptation of micro organism to their host crops.The nodH gene, which encodes sulfotransferase involved in the transfer of a sulfate group to the decreasing end of the Nod aspects, was discovered in the A. glycyphyllos symbionts genomes by the PCR strategy. The 491 bp fragment of the nodH gene was amplified in all six studied strains. Sequencing of the PCR products verified their similarity to the nodH genes of rhizobia, in which sulfated Nod factors were chemically supported. The alignment of nodH gene sequences of liquorice milkvetch nodulators and reference rhizobia exhibited one hundred eighty continual positions, 80 variable but parsimony uninformative and 231 parsimony educational ones. The ti/television set ratio factors to a minor bias toward transitions in the analyzed alignment. The acquired in this operate nodH gene sequences had been the most closely related to individuals of the M. ciceri, M. opportunistum and M. australicum sb. biserrulae strains , and next, to the sequences of M. huakuii symbiont of A. sinicus and Mesorhizobium sp. N33 symbiont of Oxytropis arctobia . Nucleotide identity of the nodH genes of A. glycyphyllos symbionts and other nodule bacteria, incorporated in the evaluation, was in the selection from 67 to seventy four%. The phylogenetic examination of the nodH sequences resulted in the NJ tree, offered in Fig three. All six liquorice milkvetch nodulators had been grouped in a single, limited, monophyletic cluster . In a sister, clearly independent clade, symbiovar biserrulae strains have been put AS-604850and, at the base of this cluster, M. huakuii was found in a different, highly supported department. All these germs shaped a strongly supported clade which suggests its robustness. Exterior of this cluster, the other rhizobial strains harboring nodH genes have been positioned.
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