Metatranscriptomics and genomic context of microbial genes related to biogeochemical cycles in mangroves

Abstract

Among the terrestrial ecosystems, some call our attention due to the particular combination of environmental parameter, resulting in the evolution of specie capable to colonize restrictively such environments. mangroves constitute a biome composed by species of plants, animals and microorganisms which interact in an environment characterized by occurrence in the interface between land and sea in inter-tropical regions. Such location doe confer unique conditions to this niche, mainly related with salinity, frequent anaerobiosis and seasonal variations in the availability of nutrients. In mangroves, bacteria, archaea and fungi constitute 91% of the total biomass; however, little is known about the functioning of the microbial groups in mangroves. In this way, this proposal aim to study by innovative technologies (metatranscriptomics and genomic context analysis) the functional microbial communities in two mangroves located in the State of Sao Paulo (already targeted by our group in previous studies). The gene expression will be determined by the massive sequencing of RNA (Illumina technology), aiming to identify genes expressed by the resident microbial community under distinct stages of mangroves preservation. Concerning the genomic context analysis, it will be performed the detection of genes related with biogeochemical cycling of carbon (mcrA), nitrogen (hzo, nifD, nifH, nirK, nirS, nosZ) and sulfur (aprA, dsrB), in metagenomic libraries already obtained with DNA extracted from the targeted mangroves (with 20Kb average for inserts sizes). It will support on inferences linking the phylogeny to function in the studied area. In sum, information will be collected about these functional communities in an innovative way, not only describing a single gene, but its expression in mangroves, and the genomic context in which does occur in the microbial community residing in this environment. (AU)