Open AccessDual effect of M esorhizobium loti T3SS functionality on the symbiotic process
Author(s) -
Sánchez Cintia,
Mercante Virginia,
Babuin María F.,
Lepek Viviana C.
Publication year - 2012
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2012.02545.x
Subject(s) - lotus japonicus , type three secretion system , biology , lotus , effector , mutant , secretion , microbiology and biotechnology , botany , genetics , biochemistry , gene
M esorhizobium loti MAFF 303099 has a functional type III secretory system ( T3SS ) involved in the nodulation process on L otus tenuis and L otus japonicus . Four putative M . loti T3SS effectors ( M lr6358, M lr6331, M lr6361, and M lr6316) have been previously described, and it has been demonstrated that the N ‐terminal regions of M lr6361 and M lr6358 mediate the secretion via a T3SS . Here, we demonstrate the capacity of M lr6316 and M lr6331 N ‐terminal regions to direct the secretion of a translational fusion to a reporter peptide through T3SS . By using single, double, and triple mutants, we demonstrated the positive and negative participation of some of these proteins in the determination of competitiveness on L otus spp. Low competitiveness values correlated with low nodulation efficiency for a mutant deficient in three of the putative M . loti effectors. Our data suggest that the net effect of M . loti T3SS function on symbiotic process with Lotus results from a balance between positive and negative effects.