Microbial community in the high canopy of the Bornean tropical rainforest: molecular diversity

Abstract

Fungi are the most diverse organisms on Earth. However, lots of fungi are still not identified. Failures to correctly identify fungi prevents the progression on the study of species diversity, fungal-fungal interactions, and environmental adaptations. Analysis of data generated with molecular methods can be efficiently applied for identification of fungi. In this study molecular methods were used to identify different fungi from poorly explored habitats such as rain forest of Brunei, Borneo. Borneo has significant amount of biodiversity that is understudied and available for exploration. Therefore, Borneo rainforest is a remarkable area for researcher to explore microorganisms like fungi. Identification and study of unknown fungi species can lead to discover of new sources of enzymes and bioactive metabolites. Borneo is a home of dipterocarp species and ants which spend most of their time on Dipterocarpacea canopies, exploring for food or nesting grounds. For this reason, samples from a different region of ant territories like their nest, leaves phyllosphere (including epiphyte and endophyte), and the ants themselves were collected and isolated. The ITS1 and 2 were combined with tef1 (translation elongation factor-1 alpha) and used as markers for identification of fungi. The DNA sequences were compared with other published sequences via NCBI BLAST. The sequences were aligned via MAFFT. For phylogenetic inference, maximum parsimony analysis was used by using MEGA X. A large part of 524 samples is composed of Ascomycota, while 14 samples belong to Basidiomycota and Mucoromycota. The strains were divided into groups according to their isolated area which are phyllosphere, epiphytic & endophytic fungi from Shorea sp. and Ficus sp. , C. bruneiensis and C. explodens nests and phylogenetic trees were constructed. Species from orders Hypocreales (f.e. Trichoderma sp., Fusarium sp.), Xylariales (f.e. Pestalotiopsis sp. and Arthrinium sp.) and Eurotiales (f.e. Penicillium sp.) were found dominating. Yeasts are mainly represented by Debaryomyces and Candida genera from Saccharomycetales order. The study showed that, ants nests possess a less biodiversity than leaves. On the other hand, nests are mostly home of black fungi from several taxonomic groups.

Fungi are the most diverse organisms on Earth. However, lots of fungi are still not identified. Failures to correctly identify fungi prevents the progression on the study of species diversity, fungal-fungal interactions, and environmental adaptations. Analysis of data generated with molecular methods can be efficiently applied for identification of fungi. In this study molecular methods were used to identify different fungi from poorly explored habitats such as rain forest of Brunei, Borneo. Borneo has significant amount of biodiversity that is understudied and available for exploration. Therefore, Borneo rainforest is a remarkable area for researcher to explore microorganisms like fungi. Identification and study of unknown fungi species can lead to discover of new sources of enzymes and bioactive metabolites. Borneo is a home of dipterocarp species and ants which spend most of their time on Dipterocarpacea canopies, exploring for food or nesting grounds.