ABSTRACT
BACKGROUND: Rahnella perminowiae S11P1 and Variovorax sp. S12S4 are two plant growth-promoting rhizobacteria that were previously isolated from the rhizosphere of Crocus sativus L. (saffron), and have demonstrated interesting PGP activities and promising results when used as inoculants in field trials. To further elucidate the molecular mechanisms underlying their beneficial effects on plant growth, comprehensive genome mining of S11P1 and S12S4 and comparative genomic analysis with closely related strains were conducted. RESULTS: Functional annotation of the two strains predicted a large number of genes involved in auxin and siderophore production, nitrogen fixation, sulfur metabolism, organic acid biosynthesis, pyrroloquinoline quinone production, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, volatile organic compounds production, and polyamine biosynthesis. In addition, numerous genes implicated in plant-bacteria interactions, such as those involved in chemotaxis and quorum sensing, were predicted. Moreover, the two strains carried genes involved in bacterial fitness under abiotic stress conditions. Comparative genomic analysis revealed an open pan-genomic structure for the two strains. COG annotation showed that higher fractions of core and accessory genes were involved in the metabolism and transport of carbohydrates and amino acids, suggesting the metabolic versatility of the two strains as effective rhizosphere colonizers. Furthermore, this study reports the first comparison of Multilocus sequence analysis (MLSA) and core-based phylogenies of the Rahnella and Variovorax genera. CONCLUSIONS: The present study unveils the molecular mechanisms underlying plant growth promotion and biocontrol activity of S11P1 and S12S4, and provides a basis for their further biotechnological application in agriculture.
Subject(s)
Alphaproteobacteria , Crocus , Rahnella , Rhizosphere , Plant Development , Bacteria , Genomics , Plant Roots/metabolism , Soil MicrobiologyABSTRACT
We report the draft genome sequences of plant growth-promoting Rahnella perminowiae strain S11P1, Variovorax sp. strain S12S4, and Pseudomonas sp. strains S11A4 and S11P7, which were isolated from saffron (Crocus sativus L.) rhizosphere. Several genes were predicted to be involved in auxin production, phosphate solubilization, and other specialized functions in plant growth and defense.
ABSTRACT
We report the draft genome sequences of three Pseudomonas chengduensis strains isolated from the sand dunes of the Merzouga (MDMC17 strain) and Erg Lihoudi (MDMC216 and MDMC224 strains) regions in the Moroccan desert. These bacteria are able to tolerate the harsh environmental conditions of the desert ecosystem.
ABSTRACT
We report the draft genome sequences of Enterobacter hormaechei subsp. xiangfangensis strains MDMC82 and MDMC76, which were isolated from the sand dunes of the Merzouga desert in the Moroccan Sahara. These bacteria are able to tolerate the harsh environmental conditions of the Moroccan desert.