Targeted ITS1 sequencing unravels the mycodiversity of deep-sea sediments from the Gulf of Mexico

Abstract

Fungi from marine environments have been significantly less studied than terrestrial fungi. This study describes distribution patterns and associated habitat characteristics of the mycobiota of deep-sea sediments collected from the Mexican exclusive economic zone (EEZ) of the Gulf of Mexico (GoM), ranging between 1000 and > 3500 m depth. Internal Transcribed Spacer 1 (ITS1) amplicons were sequenced by Illumina MiSeq. From 29 stations sampled across three annual campaigns, a total of 4421 operational taxonomic units (OTUs) were obtained, indicating a high fungal richness. Most OTUs assignments corresponded to Ascomycota, unidentified fungi and Basidiomycota. The majority of the stations shared a mere 31 OTUs, including the worldwide reported genera Penicillium, Rhodotorula and Cladosporium. Both a transient and a conserved community were identified, suggesting their dependence on or adaptation to the habitat dynamics, respectively. The differences found in fungal richness and taxonomic compositions were correlated principally with latitude, carbon and carbonates content, and terrigenous content, which could be the potential drivers that delimit fungal distribution. This study represents an expansion of our current knowledge on the biogeography of the fungal community from deep-sea sediments, and identifies the geographic and physicochemical properties that delimit fungal composition and distribution in the GoM.