Project description:The Burkholderia cepacia complex (Bcc) comprises strains with a virulence potential toward immunocompromised patients as well as plant growth-promoting rhizobacteria (PGPR). Owing to the link between quorum sensing (QS) and virulence, most studies among Bcc species have been directed toward QS of pathogenic bacteria. We have investigated the QS of B. ambifaria, a PGPR only infrequently recovered from patients. The cepI gene, responsible for the synthesis of the main signaling molecule N-octanoylhomoserine lactone (C8 -HSL), was inactivated. Phenotypes of the B. ambifaria cepI mutant we observed, such as increased production of siderophores and decreased proteolytic and antifungal activities, are in agreement with those of other Bcc cepI mutants. The cepI mutant was then used as background strain for a whole-genome transposon-insertion mutagenesis strategy, allowing the identification of 20 QS-controlled genes, corresponding to 17 loci. The main functions identified are linked to antifungal and antimicrobial properties, as we have identified QS-controlled genes implicated in the production of pyrrolnitrin, burkholdines (occidiofungin-like molecules), and enacyloxins. This study provides insights in the QS-regulated functions of a PGPR, which could lead to beneficial potential biotechnological applications.
| S-EPMC3633348 | biostudies-literature
Project description:Streptomyces as biocontrol agents of phytopathogens
Project description:Many Trichoderma spp. are successful plant beneficial microbial inoculants due to their ability to act as biocontrol agents with direct antagonistic activities to phytopathogens, and as biostimulants capable of promoting plant growth. This work investigates the effects of treatments with three selected Trichoderma (strains T22, TH1 and GV41) to strawberry plants on the productivity and proteome of the formed fruit. Proteomic analysis of fruits,harvested from the plants previously treated with Trichoderma and control plants was performed by using a TMT-based protein quantification strategy. Bioinformatic analysis of the differential proteins accumulation in fruits, harvested from the treated plants, revealed a central network of interacting molecular species, that demonstrated the modulation of different plant physiological processes following the microbial inoculation.
Project description:An antifungal aroma substance, 2-phenylethanol (PEA), was isolated from antagonistic yeast strain Kloeckera apiculata extract. Microarry were used to analyse its role citrus. We used microarrays to detail the global programme of gene expression underlying Citrus were treated with 1.0x108 cells/ml K. apiculata (KA), PEA (0.15%), the extract (1000xdilute) and control (CK) for 24 h,
