Bioprospection of argentinean soils for genes involved in the nitrogen metabolism

P. CALDEROLI; AGUILAR, O. M.; COLLAVINO, M.M; RAMOS, E

Rosario, Argentina

Congreso; IX Congreso Argentino de Microbiología General (SAMIGE); 2013

SAMIGE

Nowadays, microbial communities can be examined by their metagenomes which is technically possible by applying high-throughput sequencing technologies. We performed a functional metagenomic analysis of Argentinean´s soils to retrieve functional genes involved in the biogeochemical nitrogen cycle. In order to focus on particular metabolic pathways such as nitrogen fixation, nitrification, reduction of nitrate/nitrite and denitrification, it was necessary to select genes known to be molecular markers involved in this processes such as: nifH, nifD, narG, napA, nirA, nirB, amoA, nirK, nirS, norB and nosZ. The soil metagenomes analyzed from five different sites from the Argentinean Pampaean region under three different types of land use (non-tillage, tillage and non cultivated) and two type of soil sources (bulk and rhizospheric) resulted in 36 shotgun metagenome libraries totaling 17.8 Mi reads (7.7 Gb) using 454-FLX technology. This set of data was processed through a Bioinformatic Platafform (MGX-Gui), applying tools such as BlastX against the EggNOG database (version 3.0) and also against a robust database composed of homologous sequences to the genes of our interest. The web tool FunGene (http://fungene.cme.msu.edu) was used to retrieve the amino acid sequences used for the database construction. This database provided also taxonomic information of the best hits that were retrieved from the BlastX.