INSTITUTO DE PROCESOS BIOTECNOLOGICOS Y QUIMICOS ROSARIO
Unidad Ejecutora - UE
congresos y reuniones científicas
Putative new mechanisms involved in wheat growth promotion and biocontrol were discovered by inspecting PGPB genomes
BLANCATO, VICTOR; TORRES MANNO, MARIANO A.; DAURELIO, LUCAS D.; GIZZI FERNAN; ESPARIZ, MARTÍN
Congreso; LVII SAIB Meeting - XVI SAMIGE Meeting; 2021
Wheat is one of the principal cereals of Argentine agriculture and its cultivation is considered strategic in rotations due to its contribution to the sustainability of the soils. Plant growth promoting bacteria (PGPB) can colonize the rhizospheres of plants, and act as biofertilizers and antagonists of pathogens (biopesticides). Due to this, they emerged as a technological alternative for a sustainable agricultural exploitation, as a replacement for agrochemicals. Many of these microorganisms belong to the genus Bacillus and proliferate in soils exploited agriculturally. In this work we characterize six wheat associated strains presenting PGPB and biocontrol properties belonging to Bacillus velezensis and Priestia megaterium (formerly known as Bacillus megaterium). The whole genome sequences were determined using Illumina and PacBio technology and the taxonomy identity was defined using Multiple Locus Sequences Analysis (MLSA) and Average Nucleotide Identity (ANI). A comparative genomic analysis was processed in order to identify the plant growth promoting mechanism of these strains. Known secondary metabolite and general PGP pathways were searched first using the GeM-Pro algorithm. This pathway search upon the six strains and available genomes from B. velezensis and P. megaterium groups expose some of the possible mechanisms in growth promoting and biocontrol. Additional potential pathways were searched using the antiSMASH platform resulting in potential new pathways for P. megaterium and B. velezensis isolated strains. Another comparative genomic analysis with these new pathways was performed with the available genomes with the aim of finding the exclusive genes that correspond with the differential plant growth promoting phenotypes. As result, we found exclusive pathways in the P. megaterium strains involving Non-Ribosomal Peptide Synthases (NRPS) and Polyketide Synthase (PKS) that were not detected in the non redundant nucleotide GenBank database. Secondly, thanks to the PacBio technology, we confirm that these gene clusters are coded in two different plasmids. This may suggest that these are recently acquired gene clusters as a result of adaptation to the environment.