ADVANCES IN THE FUNCTIONAL CHARACTERIZATION OF ANTIMICROBIAL PEPTIDE SNAKIN-1 FROM ALFALFA

GARCÍA G.; AYUB NICOLAS; SETTEN L; ALMASIA, NATALIA INÉS; CECILIA VAZQUEZ ROVERE; SOTO GABRIELA

Mendoza

Congreso; XLVIII Reunión Anual de la SAIB; 2012

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

Medicago sativa sp., commonly named alfalfa, is one of the mostimportant forage crops in the world. We obtained several transgenicevents of alfalfa over expressing a putative broad-spectrumantimicrobial alfalfa peptide snakin-1 (MsSN1). As Medicagosativa establishes a symbiotic relationship with soil microorganismswe wonder if the overexpression of this gene inhibits pathogens andbeneficial microorganisms too. We evaluate the action spectrum andfound that the pattern is not random suggesting a co-evolutionprocess. We also identified some Pseudomonas fluorescens Pf-5 kmmutants growing on LB supplemented with MsSN1extract. Westudied those mutants in order to determine the gene which isresponsible of snakin-1 sensibility in bacteria, and identified aputative target of this peptide. We also analyzed the presence ofnodules in transgenic plants. Overexpression seems not to affectSinorhizobium nodulation but increase the resistance to fungaldiseases. This evidence indicates that snakin-1 is a useful gene toincorporate disease resistance within alfalfa elite germoplasm.