Engineered ACC deaminase-expressing free-living cells of Mesorhizobium loti show increased nodulation efficiency and competitiveness on Lotus spp.

• Autores: Conforte, V.P.; Echeverria, M.; Sánchez, C.; Ugalde, R.A.; Menéndez, A.B.; Lepek, V.C.
• Año de publicación: 2010
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: J. Gen. Appl. Microbiol. 2010;56(4):331-338
• Materia: ACC deaminase; Competitiveness; Ethylene; Lotus; Mesorhizobium loti; 1 aminocyclopropanecarboxylic acid; 1 aminocyclopropanecarboxylic acid deaminase; deaminase; ethylene; unclassified drug; 1-aminocyclopropane-1-carboxylate deaminase; lyase; article; bacterial cell; bacterium competence; controlled study; enzyme activity; enzyme degradation; forage; genetic engineering; legume; Lotus; Mesorhizobium loti; nodulation; nonhuman; plant chromosome; promoter region; protein expression; Rhizobiaceae; strain difference; structural gene; symbiosis; wild type; Alphaproteobacteria; enzymology; genetics; microbiology; plant root; symbiosis; Lotus corniculatus var. japonicus; Lotus tenuis; Mesorhizobium loti; Alphaproteobacteria; Carbon-Carbon Lyases; Lotus; Plant Roots; Symbiosis
• Institución: Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales

Ethylene inhibits the establishment of symbiosis between rhizobia and legumes. Several rhizobia species express the enzyme ACC deaminase, which degrades the ethylene precursor 1-cyclopropane-1-carboxilate (ACC), leading to reductions in the amount of ethylene evolved by the plant. M. loti has a gene encoding ACC deaminase, but this gene is under the activity of the NifA-RpoN- dependent promoter; thus, it is only expressed inside the nodule. The M. loti structural gene ACC deaminase (acdS) was integrated into the M. loti chromosome under a constitutive promoter activity. The resulting strain induced the formation of a higher number of nodules and was more competitive than the wild-type strain on Lotus japonicus and L. tenuis. These results suggest that the introduction of the ACC deaminase activity within M. loti in a constitutive way could be a novel strategy to increase nodulation competitiveness of the bacteria, which could be useful for the forage inoculants industry.
Fil:Conforte, V.P. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Echeverria, M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Ugalde, R.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Menéndez, A.B. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
Fil:Lepek, V.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.