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Phenotypic variation in Azospirillum brasilense exposed to starvation
Author(s) -
Lerner Anat,
Valverde Angel,
CastroSowinski Susana,
Lerner Hadas,
Okon Yaacov,
Burdman Saul
Publication year - 2010
Publication title -
environmental microbiology reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.229
H-Index - 69
ISSN - 1758-2229
DOI - 10.1111/j.1758-2229.2010.00149.x
Subject(s) - azospirillum brasilense , biology , phenotype , bacteria , microbiology and biotechnology , starvation , genetics , strain (injury) , dna , microbial inoculant , gene , anatomy , endocrinology
Summary Bacteria have developed mechanisms that allow them maintaining cell viability during starvation and resuming growth when nutrients become available. Among these mechanisms are adaptive mutations and phase variation, which are often associated with DNA rearrangements. Azospirillum brasilense is a Gram‐negative, nitrogen‐fixing, plant growth‐promoting rhizobacterium. Here we report phenotypic variants of A. brasilense that were collected after exposure to prolonged starvation or after re‐isolation from maize roots. The variants differed in several features from the parental strains, including pigmentation, aggregation ability, EPS amount and composition and LPS structure. One of the phenotypic variants, overproducing EPS and showing an altered LPS structure, was further characterized and showed differential response to several stresses and antibiotics relative to its parental strain. Characterization of the variants by repetitive‐PCR revealed that phenotypic variation was often associated with DNA rearrangements.