Mesorhizobium metallidurans sp. nov., a metal-resistant symbiont of Anthyllis vulneraria growing on metallicolous soil in Languedoc, France.

A polyphasic taxonomic approach was used to characterize 31 rhizobial isolates obtained from Anthyllis vulneraria, a metallicolous legume species, growing close to a zinc mine in the south of France (Saint Laurent le Minier). Comparative analysis of nearly full-length 16S rRNA gene sequences showed that these Gram-negative bacteria belonged to the genus Mesorhizobium and that they were related most closely to Mesorhizobium tianshanense ORS 2640(T). The phylogenetic relationships of these isolates with other Mesorhizobium species were confirmed by sequencing and analysis of the recA and atpD genes, which were used as alternative chromosomal markers.