Diversity of Microbial Carbohydrate-Active enZYmes (CAZYmes) Associated with Freshwater and Soil Samples from Caatinga Biome
- 840 Downloads
Semi-arid and arid areas occupy about 33% of terrestrial ecosystems. However, little information is available about microbial diversity in the semi-arid Caatinga, which represents a unique biome that extends to about 11% of the Brazilian territory and is home to extraordinary diversity and high endemism level of species. In this study, we characterized the diversity of microbial genes associated with biomass conversion (carbohydrate-active enzymes, or so-called CAZYmes) in soil and freshwater of the Caatinga. Our results showed distinct CAZYme profiles in the soil and freshwater samples. Glycoside hydrolases and glycosyltransferases were the most abundant CAZYme families, with glycoside hydrolases more dominant in soil (∼44%) and glycosyltransferases more abundant in freshwater (∼50%). The abundances of individual glycoside hydrolase, glycosyltransferase, and carbohydrate-binding module subfamilies varied widely between soil and water samples. A predominance of glycoside hydrolases was observed in soil, and a higher contribution of enzymes involved in carbohydrate biosynthesis was observed in freshwater. The main taxa associated with the CAZYme sequences were Planctomycetia (relative abundance in soil, 29%) and Alphaproteobacteria (relative abundance in freshwater, 27%). Approximately 5–7% of CAZYme sequences showed low similarity with sequences deposited in non-redundant databases, suggesting putative homologues. Our findings represent a first attempt to describe specific microbial CAZYme profiles for environmental samples. Characterizing these enzyme groups associated with the conversion of carbohydrates in nature will improve our understanding of the significant roles of enzymes in the carbon cycle. We identified a CAZYme signature that can be used to discriminate between soil and freshwater samples, and this signature may be related to the microbial species adapted to the habitat. The data show the potential ecological roles of the CAZYme repertoire and associated biotechnological applications.
KeywordsMetagenomics Caatinga CAZYome Carbohydrate-active enzymes (CAZYmes) Biomass conversion Environmental microbial diversity
This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, 475088/2012-3-APQ) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, 23038.009420/2012-71). Thanks to Dr. Carlos Rezende and his team from the Universidade Estadual do Norte Fluminense for help with sampling and mapping.
- 1.Leal I, Tabareli M, Cardos da Silva JM (2003) Ecologia e conservação da caatinga, 2nd ed. Editora Universitária UFPEGoogle Scholar
- 2.Queiroz LP de, Rapini A, Giulietti AM (2006) Towards greater knowledge of the Brazilian semi-arid biodiversity, 1st edn. Ministério do Meio AmbienteGoogle Scholar
- 3.Ministério do Meio Ambiente Áreas Prioritárias para Conservação, Uso Sustentável e Repartição de Benefícios da Biodiversidade BrasileiraGoogle Scholar
- 9.Ben-David EA, Zaady E, Sher Y, Nejidat A (2011) Assessment of the spatial distribution of soil microbial communities in patchy arid and semi-arid landscapes of the Negev Desert using combined PLFA and DGGE analyses. FEMS Microbiol Ecol 76:492–503. doi: 10.1111/j.1574-6941.2011.01075.x CrossRefPubMedGoogle Scholar
- 32.Nayfach S, Pollard KS (2015) Average genome size estimation improves comparative metagenomics and sheds light on the functional ecology of the human microbiome. Genome Biol 16:51. doi: 10.1186/s13059-015-0611-7
- 55.Hart GW, Akimoto Y (2009) The O-GlcNAc modification. In: Varki A, Cummings RD, Esko JD et al. (eds) Essentials of glycobiology, 2nd edn. Cold Spring Harbor Laboratory Press, New York, p 784Google Scholar
- 59.Zhou J, Xia B, Huang H et al. (2003) Bacterial phylogenetic diversity and a novel candidate division of two humid region, sandy surface soils. http://www.sciencedirect.com/science/article/pii/S003807170300124X. Accessed 26 April 2016
- 77.Kanokratana P, Eurwilaichitr L, Pootanakit K, Champreda V (2015) Identification of glycosyl hydrolases from a metagenomic library of microflora in sugarcane bagasse collection site and their cooperative action on cellulose degradation. J Biosci Bioeng 119:384–391. doi: 10.1016/j.jbiosc.2014.09.010 CrossRefPubMedGoogle Scholar