Ecological and evolutionary significance of novel protist lineages

VII_ECOP-ISOP

Published in the European Journal of Protistology as part of the VII European Congress of Protistology special issue

Ecological and evolutionary significance of novel protist lineages

Javier del Campo, Laure Guillou, Elisabeth Hehenberger, Ramiro Logares, Purificación López-García, Ramon Massana

Environmental molecular surveys targeting protist diversity have unveiled novel and uncultured lineages in a variety of ecosystems, ranging from completely new high-rank lineages, to new taxa moderately related to previously described organisms. The ecological roles of some of these novel taxa have been studied, showing that in certain habitats they may be responsible for critical environmental processes. Moreover, from an evolutionary perspective they still need to be included in a more accurate and wider understanding of the eukaryotic tree of life. These seminal discoveries promoted the development and use of a wide range of more in-depth culture-independent approaches to access this diversity, from metabarcoding and metagenomics to single cell genomics and FISH. Nonetheless, culturing using classical or innovative approaches is also essential to better characterize this new diversity. Ecologists and evolutionary biologists now face the challenge of apprehending the significance of this new diversity within the eukaryotic tree of life.

Molecular diversity and distribution of marine fungi

BMfungi

Published in Proceedings of the Royal Society B

Molecular diversity and distribution of marine fungi across 130 European environmental samples

Thomas A. Richards, Guy Leonard, Frédéric Mahé, Javier del Campo, Sarah Romac, Meredith D. M. Jones, Finlay Maguire, Micah Dunthorn, Colomban De Vargas, Ramon Massana, Aurélie Chambouvet

Environmental DNA and culture-based analyses have suggested that fungi are present in low diversity and in low abundance in many marine environments, especially in the upper water column. Here, we use a dual approach involving high-throughput diversity tag sequencing from both DNA and RNA templates and fluorescent cell counts to evaluate the diversity and relative abundance of fungi across marine samples taken from six European near-shore sites. We removed very rare fungal operational taxonomic units (OTUs) selecting only OTUs recovered from multiple samples for a detailed analysis. This approach identified a set of 71 fungal ‘OTU clusters’ that account for 66% of all the sequences assigned to the Fungi. Phylogenetic analyses demonstrated that this diversity includes a significant number of chytrid-like lineages that had not been previously described, indicating that the marine environment encompasses a number of zoosporic fungi that are new to taxonomic inventories. Using the sequence datasets, we identified cases where fungal OTUs were sampled across multiple geographical sites and between different sampling depths. This was especially clear in one relatively abundant and diverse phylogroup tentatively named Novel Chytrid-Like-Clade 1 (NCLC1). For comparison, a subset of the water column samples was also investigated using fluorescent microscopy to examine the abundance of eukaryotes with chitin cell walls. Comparisons of relative abundance of RNA-derived fungal tag sequences and chitin cell-wall counts demonstrate that fungi constitute a low fraction of the eukaryotic community in these water column samples. Taken together, these results demonstrate the phylogenetic position and environmental distribution of 71 lineages, improving our understanding of the diversity and abundance of fungi in marine environments.

Microbe Coexistence and Coevolution in a Changing Ocean

 girona

Gordon Research Seminar on Marine Microbes

Chairs: Javier del Campo & Bryndan Durham

June 18-19, 2016
PGA Catalunya Business and Convention Centre
Girona, Catalonia

The Gordon Research Seminar on Marine Microbes is a unique forum for graduate students, post-docs, and other scientists with comparable levels of experience and education to present and exchange new data and cutting edge ideas.

Marine microorganisms interact constantly among themselves and with other members of the trophic network. These interactions define their evolutionary fate and underlie the biogeochemical fluxes that will drive ecological processes in current and future oceans. The seminar will bring together microbial ecologists and evolutionary biologists to discuss and debate about where, when and why marine microbes interact, who are the main players mediating these processes, and what will be the resulting evolutionary and ecological outputs.

Apply now!

Applications for this meeting must be submitted by May 21, 2016. Please apply early, as some meetings become oversubscribed (full) before this deadline. Note: Applications for oversubscribed meetings will only be considered by the Conference Chair if more seats become available due to cancellations.