Novel symbiovars ingae, lysilomae and lysilomaefficiens in bradyrhizobia from tree-legume nodules

Syst Appl Microbiol. 2023 May 11;46(4):126433. doi: 10.1016/j.syapm.2023.126433. Online ahead of print.ABSTRACTInga vera and Lysiloma tree legumes form nodules with Bradyrhizobium spp. from the japonicum group that represent novel genomospecies, for which we describe here using genome data, symbiovars lysilomae, lysilomaefficiens and ingae. Genes encoding Type three secretion system (TTSS) that could affect host specificity were found in ingae but not in lysilomae nor in lysilomaefficiens symbiovars and uptake hydrogenase hup genes (that affect nitrogen fixation) were observed in bradyrhizobia from the symbiovars ingae and lysilomaefficiens. nolA gene was found in the symbiovar lysilomaefficiens but not in strains from lysilomae. We discuss that multiple genes may dictate symbiosis specificity. Besides, toxin-antitoxin genes were found in the symbiosis islands in bradyrhizobia from symbiovars ingae and lysilomaefficiens. A limit (95%) to define symbiovars with nifH gene sequences was proposed here.PMID:37207476 | DOI:10.1016/j.syapm.2023.126433

Source: Systematic and Applied Microbiology - May 19, 2023 Category: Microbiology Authors: Diana Hern ández-Oaxaca Karen Claro Marco A Rogel M ónica Rosenblueth Julio Martinez-Romero Esperanza Martinez-Romero Source Type: research