mesorhizobium chacoense mesorhizobium chacoense mesorhizobium chacoense is a gram-negative, aerobic, non-spore-forming, motile bacteria from the genus of mesorhizobium which was isolated from root nodules of prosopis alba in the chaco arido region in argentina. mesorhizobium chacoense scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: hyphomicrobiales family: phyllobacteriaceae genus: mesorhizobium species: m. chacoense binomial name mesorhizobium chacoensevelázquez et al. 2001 type strain cect 5336, cfbp 6713, cip 107324, dsm 17287, kctc 12945, lmg 19008, pr5, r-6566, stm 2154