Person: Martín Cereceda, María Mercedes
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First Name
María Mercedes
Last Name
Martín Cereceda
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Biológicas
Department
Genética, Fisiología y Microbiología
Area
Microbiología
Identifiers
14 results
Search Results
Now showing 1 - 10 of 14
Item Rain-fed granite rock pools in a national park: extreme niches for protists(Limnetica, 2021) Pérez Uz, María Blanca; Velasco González, Ismael; Murciano, Antonio; Sánchez Jiménez, Abel; García-Rodriguez, M.; Centeno Carrillo, Juan de Dios; Montero González, Esperanza; Muñoz Araújo, Benito; Olmedo Salinas, Cristina; Quintela Alonso, Pablo; Refoyo Román, Pablo; Williams, Richard Alexander John; Martín Cereceda, María MercedesRain-fed granite rock pools are geological landforms with a worldwide distribution. However, their role as habitats for microorganisms has been barely explored. We carried out a detailed morphological inventory of the ciliated protists in the sediments of three granite rain-fed rock pools from a Spanish National Park. The ciliate seed bank in the rock pools comprised 54 morphospecies. The species number inferred for each pool by rarefaction analysis was similar to that observed by microscopy. The most representative species were small bacterivorous ciliates, although the distribution of ciliate groups was significantly different in each rock pool. Testate amoebae were also found to be rich in species. This study demonstrates the existence of a diverse ciliate community adapted to persist in these ephemeral and extreme rock pool habitats through species resistance structures, many of which have not been described previously. The presence of competitive species in dormant stages prevents local extinctions through a sequential excystation over time. Our results provide a benchmark for studying protist and microbial biodiversity within rain-fed granite rock pools, a unique habitat that merits bio- and geo- conservation.Item Ciliates — Protists with complex morphologies and ambiguous early fossil record(Marine Micropaleontology, 2015) Dunthorn, Micah; Lipps, Jere H.; Dolan, John R.; Abboud-Abi Saab, Marie; Aescht, Erna; Bachy, Charles; Barría de Cao, María Sonia; Berger, Helmut; Bourland, William A.; Choi, Joong Ki; Clamp, John; Doherty, Mary; Gao, Feng; Gentekaki, Eleni; Gong, Jun; Hu, Xiaozhong; Huang, Jie; Kamiyama, Takashi; Johnson, Matthew D.; Kammerlander, Barbara; Kim, Sun Young; Kim, Young-Ok; la Terza, Antonietta; Laval-Peuto, Michèle; Lipscomb, Diana; Lobban, Christopher S.; Long, Hongan; Luporini, Pierangelo; Lynn, Denis H.; Macek, Miroslav; Mansergh, Robert I.; Martín Cereceda, María Mercedes; McManus, George G.; Montagnes, David J.S.; Ong'ondo, Geoffrey O.; Patterson, David J.; Pérez Uz, Blanca; Quintela Alonso, Pablo; Stoecker, Diane K.; Strüder-Kypke, Michaela C.; Trautmann, Isabelle; Utz, Laura R.P.; Vallesi, Adriana; Vd'ačný, Peter; Warren, Alan; Weisse, Thomas; Wickham, Stephen A.; Yi, Zhenzhen; Zhang, Wuchang; Zhan, Zifeng; Zufall, Rebecca; Agatha, SabineSince ciliates rarely possess structures that easily fossilize, we are limited in our ability to use paleontological studies to reconstruct the early evolution of this large and ecologically important clade of protists. Tintinnids, a group of loricate (house-forming) planktonic ciliates, are the only group that has a significant fossil record. Putative tintinnid fossils from rocks older than Jurassic, however, possess few to no characters that can be found in extant ciliates; these fossils are best described as ‘incertae sedis eukaryotes’. Here, we review the Devonian fossil Nassacysta reticulata and propose that it is likewise another incertae sedis eukaryote due to the lack of any unambiguous ciliate characters. Future tintinnid fossil descriptions would be most helpful if: (i) neutral terminology is used in the descriptions but ciliate-specific terminology in the interpretations; (ii) the current ciliate classification is used, although fossil data may expand or modify classifications based on modern forms; (iii) close collaboration with specialists studying extant ciliates is done; and (iv) editors include an expert of extant ciliates in the review process.Item Complexity of river ciliate communities at a national park highlights the need for microbial conservation(Aquatic Conservation: Marine and Freshwater Ecosystems, 2018) Quintela Alonso, Pablo; Pérez‐Uz, Blanca; Sánchez Jiménez, Abel; Murciano Cespedosa, Antonio; Centeno, Juan D.; García-Rodríguez, Manuel; Montero, Esperanza; Muñoz Araújo, Benito; Olmedo Salinas, Cristina; Refoyo Román, Pablo; Velasco González, Ismael; Martín Cereceda, María Mercedes1.Microorganisms play pivotal roles in aquatic ecosystems. Free‐living protists are the main components of the eukaryotic microbial communities at the base of freshwater ecosystems. Ciliate grazing channels a large proportion of organic matter into multicellular organisms. Surprisingly, ciliates and other microorganisms are neglected in global conservation schemes. 2. Interstitial ciliates were sampled in three sites of varying human pressure on the River Manzanares (La Pedriza National Park, Spain). Abundances of trophic groups and species were adjusted to a generalized linear model (GLM Poisson regression). 3.Ciliate communities were rich in species (74 morphotypes) and although traditional microscopy retrieved a high number of species that appeared only once or in low numbers, rarefaction analyses estimated much larger species richness. These results illustrate that rarefaction assays are a useful first step for exploring the extent of the ciliate cryptic diversity in freshwater ecosystems. 4.Benthic ciliate communities changed significantly, both spatially and at a short temporal scale. The fluctuating nature of the community was manifested by the presence of many ephemeral species at the same river site, revealing a complex and transient community structure. No significant short‐term changes were observed in the physical–chemical properties. Therefore, even slight differences in the abiotic variables may cause rapid shifts of ciliate species. 5.Overall, human pressure had an effect on the interstitial (or benthic) ciliates that resulted in a reduction of species richness and their abundance.Item Influencia de la temperatura sobre la asimetría de pilancones en ambiente granítico. Aplicación de un modelo de regresión lineal(Boletín de la Sociedad Geológica Mexicana, 2017) García Rodríguez, Manuel; Sánchez Jiménez, Abel; Murciano Cespedosa, Antonio; Pérez Uz, María Blanca; Martín Cereceda, María MercedesLas pilas representan un tipo de forma presente en casi todos los ambientes climáticos. El trabajo estudia el papel de los ciclos térmicos como un agente importante del modelado y asimetría que presentan las paredes de las pilas en un clima Mediterrá- neo templado - frío. El estudio se ha realizado en el macizo granítico de la Pedriza de Manzanares, zona protegida de gran valor ambiental, incluida en el Parque Nacional de la Sierra de Guadarrama (Madrid, España). El análisis de la variabilidad térmica mediante modelos de regresión perió- dica múltiple, pone de manifiesto la influencia de los ciclos diario y anual en función de las orientaciones norte y sur de las paredes de las pilas. Un modelo matemático de regresión lineal muestra cómo la variabilidad térmica diaria influye en la alteración de las paredes de las pilas, generando superficies planas o de concavidad más o menos pronunciada. El trabajo también establece relaciones entre el grado de alteración de las diferentes partes de las pilas, con la presencia de líquenes y dureza relativa de la roca. Los resultados avalan la hipótesis de relación causal entre la variabilidad térmica y alteración de las paredes de las pilas según su orientación norte o sur.Item An investigation of the fine structure, cell surface carbohydrates, and appeal of the diatom Extubocellulus sp. as prey for small flagellates(Protoplasma, 2007) Martín Cereceda, María Mercedes; Williams, Richard Alexander John; Guinea Díaz, Almudena; Novarino, GianfrancoThe fine structure and surface exopolymers of a coastal planktonic nanodiatom of the sparsely reported genus Extubocellulus were studied respectively by scanning electron microscopy and confocal microscopy in conjunction with fluorescent lectins. Monitoring the suitability of the species as prey food for other protists was also investigated by video microscopy coupled with digital film. Cells are rectangular in girdle view, with a pervalvar axis longer than the apical axis. Valves are almost circular with a diameter of 2.8 to 3.6 m. The valve face bears randomly distributed areolae (ca. 50 in 10 m), which may be either open or occluded. Two small raised ocelluli occur at the apices, with a rim devoid of perforations and about 6–7 porelli. Glucose and N-acetylglucosamine moieties present on the surface of the live diatom were labelled with fluorescent lectins, and a differential pattern of distribution for both carbohydrates was observed. The potential role of fluorescent lectins as cellular probes of taxonomic value in small diatoms is compared with that of nucleotide and antibody probes. We provide the first illustrative evidence of the presence of Extubocellulus sp. in the cytoplasm of the nanoflagellate Goniomonas amphinema and of the egestion of diatom frustules. Results obtained are discussed in the light of the present knowledge of the role of carbohydrate–protein interactions in phagocytosis of prey by free-living protozoa.- Project number: 110
Item La curación de contenidos científicos como estrategia didáctica y divulgativa en Microbiología y otras áreas afines(2020) Gil-Serna, Jéssica; Arregui García-Rovés, Lucía; Guillen Maestro, Alberto; Martín Cereceda, María Mercedes; Pérez Uz, María Blanca; Serrano Barrero, Susana Lourdes; Silóniz Jiménez, María Isabel de; Vázquez Estévez, María Covadonga Inmaculada; Patiño Álvarez, Aurora Belén Item Diversity of DNA Sequences from Pathogenic and Potentially Pathogenic Eukaryotic Microorganisms in Protected Granite Mountain Rocks(Diversity, 2023) Murciano Cespedosa, Antonio; Pérez Uz, María Blanca; Williams, Richard Alexander John; Sánchez Jiménez, Abel; Martín Cereceda, María Mercedes; Velasco-González, Ismael; Lara, Enrique; Singer, David; de Cos-Gandoy, Amaya; García-Rodríguez, ManuelRain-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.- Project number: PIMCD69/23-24
Item Esto va de Micro: 10 retos, 10 mujeres(2024) Gil Serna, Jessica; Arregui García-Roves, Lucía; Ayllón Santiago, Tania; Casado Almarcha, Ana María; Craqui Cordeo, María de la Vega; Domenech Lucas, Miriam; García Romero, Sofía Ismerai; Gómez Albarrán, Carolina; Gómez Rodríguez de Guzmán, Lucía; Lago Espartero, Darío; Lizarazu Cubero, Carolina; Martín Cereceda, María Mercedes; Melguizo Ávila, Clara Del Carmen; Patiño Álvarez, Aurora Belén; Pavesio Toledano, Manuel; Pérez Uz, María Blanca; Pulido Vadillo, Mario; Racovita, Georgiana Valentina; Rey Menacho, Rubén; Sánchez López-Varela, Marta; Tajahuerce Ángel, Isabel; Valderrama Conde, María José; del Valle Romera, Ana; Vázquez Estévez, María Covadonga Inmaculada; Williams, Richard Alexander John“Esto va de Micro” es un pódcast de microbiología en el cual estudiantes de la Universidad Complutense realizan entrevistas a personas expertas en temas de interés en el campo de la microbiología. En el curso 2023/2024 quisimos aprovechar esta plataforma y poner en marcha este proyecto de innovación docente para dar visibilidad al trabajo de microbiólogas relevantes y explicar a la sociedad el papel de la microbiología en la consecución de los Objetivos de Desarrollo Sostenible. El resultado han sido 11 episodios de pódcast divulgativos que están disponibles en las plataformas de iVoox y Spotify. Item Easy Visualization of the Protist Oxyrrhis marina Grazing on a Live Fluorescently Labelled Heterotrophic Nanoflagellate(Current Microbiology, 2008) Martín Cereceda, María Mercedes; Williams, Richard Alexander John; Novarino, GianfrancoPlanktonic heterotrophic flagellates are ubiquitous eukaryotic microorganisms that play a crucial role in carbon and nutrient fluxes through pelagic food webs. Here we illustrate for the first time a grazing model of planktonic dinoflagellate, Oxyrrhis marina, on the heterotrophic nanoflagellate Goniomonas amphinema, using the DNAbinding fluorescent dye Hoechst 33342. A solution of 1 lg/mL of the fluorochrome allowed viability of the prey for at least 48 hours, provided low fluorescence quenching, and labelled the flagellate without masking the cytoplasm. After 2 hours of contact between the fluorescent prey and the predator, O. marina population had preyed on live G.amphinema at an ingestion rate of 2.2 prey Oxyrrhis-1 h-1. Results show that this model is a time-effective and inexpensive approach for the direct observation of heterotrophic flagellate grazing. The fact that prey remain alive while predation occurs, as well as the low rate of quenching, could be of help in studying the fate of realtime trophic interactions between protists in microbial webs.- Project number: 136
Item La Microbiología a debate(2021) Gil Serna, Jéssica; Arregui García-Rovés, Lucía; Belda Aguilar, Ignacio; Martín Cereceda, María Mercedes; Patiño Álvarez, Aurora Belén; Pérez Uz, María Blanca; Serrano Barrero, Susana Lourdes; Vázquez Estévez, María Covadonga