MULTIPLE WAYS TO EVADE THE BACTERIOSTATIC ACTION OF GLYPHOSATE IN RHIZOBIA INCLUDE THE MUTATION OF THE CONSERVED SERINE 90 OF THE NITROGENASE SUBUNIT NIFH TO ALANINE

LIEBRENZ K; FRARE R.; GOMEZ C.; PASCUAN C.; BRAMBILLA S.; SOLDINI D; MAGUIRE V.; RUIZ O.A.; MCCORMICK W; SOTO G.; AYUB N.

RESEARCH IN MICROBIOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2022

0923-2508

The genome resequencing of spontaneous glyphosate-resistant mutants derived fromthe soybean inoculant E109 allowed identifying genes most likely associated with theuptake (gltL and cya) and metabolism (zigA and betA) of glyphosate, as well as withnitrogen fixation (nifH). Mutations in these genes reduce the lag phase and improvenodulation under glyphosate stress. In addition to providing glyphosate resistance, theamino acid exchange Ser90Ala in NifH increased the citrate synthase activity, growthrate and plant growth-promoting efficiency of E109 in the absence of glyphosatestress, suggesting roles for this site during both the free-living and symbiotic growthstages.