A5074982947- Diatoms and Algae Research
- Paleontology and Stratigraphy of Fossils
- Aquatic Ecosystems and Phytoplankton Dynamics
- Geochemistry and Elemental Analysis
- Microbial Community Ecology and Physiology
- Marine and coastal ecosystems
- Geology and Paleoclimatology Research
- Hydrocarbon exploration and reservoir analysis
- Methane Hydrates and Related Phenomena
- Protist diversity and phylogeny
- Genomics and Phylogenetic Studies
- Biocrusts and Microbial Ecology
- Geochemistry and Geologic Mapping
- Calcium Carbonate Crystallization and Inhibition
- Ocean Acidification Effects and Responses
- Environmental and Cultural Studies in Latin America and Beyond
- Marine Toxins and Detection Methods
- Isotope Analysis in Ecology
- Freshwater macroinvertebrate diversity and ecology
- Geomagnetism and Paleomagnetism Studies
- Marine and coastal plant biology
- Marine Biology and Ecology Research
- Water Quality and Pollution Assessment
- Clay minerals and soil interactions
- Photosynthetic Processes and Mechanisms
Universidad Nacional Autónoma de México
2014-2025
Significance Cyanobacteria are known to promote the precipitation of Ca-carbonate minerals by photosynthetic uptake inorganic carbon. This process has resulted in formation carbonate deposits and a fossil record importance for deciphering evolution cyanobacteria their impact on global carbon cycle. Though mechanisms cyanobacterial calcification remain poorly understood, this is invariably thought as extracellular indirect by-product metabolic activity. Here, we show that contrary common...
The geomicrobiology of crater lake microbialites remains largely unknown despite their evolutionary interest due to resemblance some Archaean analogs in the dominance situ carbonate precipitation over accretion. Here, we studied diversity archaea, bacteria and protists alkaline Lake Alchichica from both field samples collected along a depth gradient (0–14 m depth) long-term-maintained laboratory aquaria. Using small subunit (SSU) rRNA gene libraries fingerprinting methods, detected wide...
The structure, mineralogy, and accretion processes of the modern subfossil cyanobacterial microbialites from alkaline crater lake Alchichica (Puebla, Mexico) were studied, along lake's bathymetry hydrochemistry. recent lowering level had exposed microbialitic carbonate mounds crusts, which emerged up to 2 m above water surface, while accreting present down a depth ~15 m. Morphological molecular analysis found that living mats composed diverse filamentous coccoid cyanobacteria (Nostocales,...
Cyanobacteria are thought to play a key role in carbonate formation due their metabolic activity, but other organisms carrying out oxygenic photosynthesis (photosynthetic eukaryotes) or metabolisms (e.g. anoxygenic photosynthesis, sulfate reduction), may also contribute formation. To obtain more quantitative information than that provided by classical PCR-dependent methods, we studied the microbial diversity of microbialites from Alchichica crater lake (Mexico) mining for 16S/18S rRNA genes...
Microbialites are organo-sedimentary rocks found in abundance throughout the geological record back to ~3.5 Ga. Interpretations of biological and environmental conditions under which they formed rely on comparisons with modern microbialites. Therefore, a better characterization diverse microbialites is crucial improve such interpretations. Here, we studied from three Mexican alkaline crater lakes: Quechulac, La Preciosa Atexcac. The geochemical analyses water solutions showed that were...
A unicellular cyanobacterium, strain Alchichica-D10, was isolated from microbialites of the alkaline Lake Alchichica, Mexico. The cells were short rods (3.9±0.6 µm in length and 1.1±0.1 width) forming biofilms intense emerald green colour. They exhibited red autofluorescence under UV light excitation. UV-visible absorption spectra revealed that they contain chlorophyll a phycocyanin, electron microscopy showed presence thylakoids. grew within temperature range 15-30 °C. Genomic DNA G+C...
Abstract. The search for microfossils in the geological record has been a long-term challenge. Part of problem comes from difficulty identifying such unambiguously, since they can be morphologically confused with abiotic biomorphs. One route to improve our ability correctly identify involves studying fossilization processes affecting bacteria modern settings. We studied initial stages cyanobacterial cells microbialites Lake Alchichica (Mexico), Mg-rich hyperalkaline crater lake (pH 8.9)...
Abstract Continental freshwater systems are particularly vulnerable to environmental variation. Climate change‐induced desertification and the anthropogenic exploitation of hydric resources result in progressive evaporation salinization inland water bodies many areas globe. However, how this process impacts microbial communities their activities biogeochemical cycles is poorly known. Here, we take a space‐for‐time substitution approach characterize prokaryotic eukaryotic two planktonic...
Cyanobacteria are mainly thought to induce carbonate precipitation extracellularly via their photosynthetic activity combined with the nucleation potential of exopolymeric substances. The discovery in microbialites alkaline lake Alchichica (Mexico) Candidatus Gloeomargarita lithophora, a cyanobacterium forming large amounts intracellular Mg-Ca-Sr-Ba spherules, showed that biomineralization cyanobacteria is also possible. A second isolated from same environment, Synechococcus calcipolaris G9,...
Microbialites are usually carbonate-rich sedimentary rocks formed by the interplay of phylogenetically and metabolically complex microbial communities with their physicochemical environment. Yet, biotic abiotic determinants microbialite formation remain poorly constrained. Here, we analysed structure prokaryotic eukaryotic associated microbialites occurring in several crater lakes Trans-Mexican volcanic belt along an alkalinity gradient. Microbialite size community correlated lake...
ABSTRACT Microbialites are organo‐sedimentary structures formed throughout most of the Earth history, over a wide range geological contexts, and under multitude environmental conditions affecting their composition. The carbon oxygen isotope records carbonates, which often main constituents, have been used as widespread tool for paleoenvironmental reconstructions. However, multiplicity factors that influence microbialites formation is not always properly distinguished in isotopic record, both...
Modern microbialites are often used as analogs of Precambrian stromatolites; therefore, studying the metabolic interplay within their associated microbial communities can help formulating hypotheses on formation and long-term preservation fossil record. We performed a comparative metagenomic analysis microbialite samples collected at two sites along depth gradient in Lake Alchichica (Mexico). The community structure inferred from single-copy gene family identification long-contig (>10 kb)...
Abstract. The dissolved organic carbon (DOC) reservoir plays a critical role in the C cycle of marine and freshwater environments because its size implication many biogeochemical reactions. Although it is poorly constrained, importance ancient Earth's cycles also commonly invoked. Yet DOC rarely quantified characterized modern stratified analogues. In this study, we investigated reservoirs four redox-stratified alkaline crater lakes Mexico. We analyzed concentrations isotopic compositions...
Abstract. Iron and manganese are poorly soluble elements in oxic alkaline solutions, whereas they much more under anoxic conditions. As a result, the formation of authigenic mineral phases rich Fe and/or Mn has traditionally been viewed as diagnostic global or local Here we reveal that some specific cyanobacteria very small size (< 2 µm, i.e., picocyanobacteria) can biomineralize abundant, Fe(III)-, Mn(IV)- Si-rich amorphous conditions an lake Mexico. The resulting biominerals cluster...
We investigated the structure and diversity of diatoms in communities metaphyton periphyton from wetland El Edén Ecological Reserve, Quintana Roo, Mexico. In spite close association communication between these communities, our comparisons reveal that 2 have distinct species assemblages, with being more diverse overall. fit abundance curves for metaphyton, argue results are consistent where environmental conditions play a important role than competition structuring diatom assemblages.
Chloroflexales (Chloroflexi) are typical members of the anoxygenic photosynthesizing component microbial mats and have mostly been characterized from communities associated to hot springs. Here, we report assembly five metagenome-assembled genomes (MAGs) a novel lineage found in mesophilic lithifying (microbialites) Lake Alchichica (Mexico). Genomic phylogenetic analyses revealed that bins shared 92% their genes, these genes were nearly identical despite being assembled samples collected...