Abstract
Mesorhizobium opportunistum strain WSM2075T was isolated inWestern Australia in 2000 from root nodules of the pasture legume Biserrula pelecinus that had beeninoculated with M. ciceri bv. biserrulae WSM1271. WSM2075T is an aerobic, motile, Gram negative, non-spore-forming rod that has gained the ability to nodulate B. pelecinus but is completely ineffective in N2 fixation with this host. This report reveals thegenome of M. opportunistum strain WSM2075T contains a chromosome ofsize 6,884,444 bp which encodes 6,685 protein-coding genes and 62 RNA-onlyencoding genes. This genome does not contain any plasmids but has a 455.7 kbgenomic island from Mesorhizobium ciceri bv. biserrulae WSM1271 that has been integrated into a phenylalanine-tRNA gene.