Avaliação do crescimento de acidobacterias do cerrado em diferentes polissacarídeos

Abstract

Organisms of the Acidobacteria phylum can be found commonly colonizing the soil of the Cerrado biome, which has the following characteristics: high acidity and potential toxicicity to some species. The literature has pointed to the potential of acidobacteria in the degradation of different polysaccharides and possible enzymatic activities based on metagenomic studies and available genomic libraries. In the present work, the degradation of polysaccharides: xylan, chitin, and cellulose were evaluated by seven strains of acidobacteria from Cerrado soil: AB20, AB23, AB39, AB60, AB158, AB46 and AB 29. The strains were previously isolated and stored in an ultrafreezer since 2013. The growth of Acidobacterium capsulatum obtained from a german culture collection was also evaluated (DSMZ). All strains grew during the recovery process demonstrating that they support the storage process. The results of cultivation on different carbon sources were evaluated after four weeks. Growth on chitin was generally low and absent for AB39, whereas the growth on xylan was comparable to the positive controls, except for A. capsulatum. The growth on cellulose was surprising, considering previous reports of the difficulty to grow acidobacteria on this polysaccharide. Only strains AB39 and AB158 did not grow in the medium. The present work showed that some acidobacteria from the Cerrado may produce hydrolytic enzymes with biotechnological potential.