Fungal diversity associated with Brazilian energy transmission towers

Abstract

The present work profiled the fungal community structure found in Brazilian energy transmission tower with signs of corrosion and/or biofilm formation using cloning (ITS-rRNA gene libraries) and culture-dependent technique. A total of 31 isolates comprising 10 filamentous fungi and 21 yeasts were recovered from enrichment cultures. As determined by polyphasic taxonomy 9 genera and 13 species were identified including Aspergillus fumigatus, Aspergillus niger, Candida albicans, Candida pseudointermedia, Candida tropicalis, Cryptococcus laurentii, Debaryomyces nepalensis, Exophiala dermatitidis, Fusarium sp., Fusarium solani, Paecilomyces lilacinus, Trichoderma citrinoviride, Trichoderma longibrachiatum, and Pichia guilliermondii. Metagenomic analyses based on 160 clone sequences revealed 30 operational taxonomic units (OTUs) comprising 20 OTUs of filamentous fungi and 10 OTUs of yeasts. The majority of OTUs were related to the genera Capnobotryella, Cryptococcus, Devriesia, Fellomyces, Fusarium, Kockovaella, Panaeolus, Rhodotorula, Sirobasidium, Sporobolomyces, Strelitziana and Teratosphaeria. Although members of the fungal community from transmission tower samples are ubiquitous fungi commonly found in other environments, some have been related to microbiologically-influenced corrosion of metals. Comparisons between fungal community composition obtained by both culture-dependent and independent methods highlighted the different aspects of the mycobiota, emphazising the need of complementary approaches to assess the microbial assemblage of unusual environments.