RT Journal Article T1 Diversity of DNA Sequences from Pathogenic and Potentially Pathogenic Eukaryotic Microorganisms in Protected Granite Mountain Rocks A1 Velasco-González, Ismael A1 Lara, Enrique A1 Singer, David A1 de Cos-Gandoy, Amaya A1 García-Rodríguez, Manuel A1 Murciano Cespedosa, Antonio A1 Pérez Uz, María Blanca A1 Williams, Richard Alexander John A1 Sánchez Jiménez, Abel A1 Martín Cereceda, María Mercedes AB Rain-fed mountain granite rock basins are temporary habitats conditioned by a fluctuating environment and the unpredictability of precipitation or flooding rates. These small highland freshwater habitats remain largely unexplored at the microbial level. The aim of this work is to report the presence in these habitats of genetic sequences of microbial eukaryotes that are pathogens and potential pathogens of humans, wildlife, cattle, crops as well as of other microorganisms. We sequenced the hypervariable region v4 of the 18S rDNA gene from environmental DNA of sediments taken from 21 rock basins in a National Park in Spain. More than a fifth (21%) of the eukaryotic Operational Taxonomic Units (OTUs) found are ascribed to pathogenic (within 11 Phyla) and potential pathogenic (within 1 phylum, the Chytridiomycota) microorganisms. Some OTUs retrieved are of agro-economic and public health importance (e.g., Pythium spp., Lagenidium spp., Candida spp. and Vermamoeba vermiformis). In 86% of the basins, the most abundant OTUs were affiliated to Chytridiomycota, a broad fungal group including saprozoic and parasitic taxa. Two OTUs affiliated to chytrids were significantly correlated with high concentrations of heavy metals. The high proportion of chytrid-like microbial sequences found emphasises the role of these freshwater habitats for adding knowledge regarding the ecological trade-offs of the still rather unknown Chytridiomycota. Our results show that rain-fed rock basins may be model habitats for the study and surveillance of microbial community dynamics and genetics of (mainly opportunistic) microbial pathogens. PB MDPI SN 1424-2818 YR 2023 FD 2023 LK https://hdl.handle.net/20.500.14352/100370 UL https://hdl.handle.net/20.500.14352/100370 LA eng NO Velasco-González I, Lara E, Singer D, de Cos-Gandoy A, García-Rodríguez M, Murciano A, Pérez-Uz B, Williams RAJ, Sanchez-Jimenez A, Martín-Cereceda M. Diversity of DNA Sequences from Pathogenic and Potentially Pathogenic Eukaryotic Microorganisms in Protected Granite Mountain Rocks. Diversity. 2023 Apr 25;15(5):594. NO This research was funded by Ministerio de Economía y Competitividad (MINECO- Spain), Project MICROEPICS Ref: CGL2013-40851-P/BOS 2014–2018 and Project Santander-UCM Ref: PR44/21-29928 to PI M.M.-C. E.L. was funded by the project “Atracción de talento investigador” by the Consejería de Educación, Juventud y Deporte, Comunidad de Madrid (Spain) 2017-T1/AMB-5210 and by a grant from the Swiss National Foundation for Research (SNF 31003A_143960). D.S. was funded by the Swiss NSF (P2NEP3_178543). A.S., A.M., A.C.-G., B.P.-U. and M.M.-C. are funded by the research group “Modelling, Data Analysis and Computational Tools for Biology (UCM)”; A.M. is also funded by research groups “Neurocomputing and Neurorobotics (UCM)” and “Brain Plasticity Group” (Health Research Institute of the Hospital Clínico San Carlos, IdISSC).Data Availability Statement: All V4-rDNA reads were deposited at the European nucleotide archive under the Project number PRJEB24091 NO Universidad Complutense de Madrid NO Banco de Santander NO Ministerio de Economía y Competitividad (España) NO Comunidad de Madrid NO Swiss National Foundation for Research DS Docta Complutense RD 8 abr 2025