Genetic diversity associated with N-cycle pathways in microbialites from Lake Alchichica, Mexico

A year in the life of a thrombolite: comparative metatranscriptomics reveals dynamic metabolic changes over diel and seasonal cycles

“…The ability of these microbialite-forming communities to alter their biological and geological environments has enabled these ecosystems to adapt to a wide range of environmental conditions over the course of Earth's history (Walter, 1994;Grotzinger and Knoll, 1999). Microbialites are located throughout the globe in a wide range of habitats (e.g., lacustrine, marine and hypersaline) and their ecological complexity is just now beginning to be revealed through advancements in high-throughput sequencing of the taxonomic and functional gene diversity (Breitbart et al, 2009;Khodadad and Foster, 2012;Petrash et al, 2012;Bernhard et al, 2011;Mobberley et al, 2013;Russell et al, 2014;Valdespino-Castillo et al, 2014;Sagha€ ı et al, 2015;Casaburi et al, 2016;Cerqueda-Garcia and Falcon, 2016;Chagas et al, 2016;Ruvindy et al, 2016;Warden et al, 2016;White et al, 2016;Alcantara-Hern andez et al, 2017;Louyakis et al, 2017).…”

Exploring Biogeochemistry and Microbial Diversity of Extant Microbialites in Mexico and Cuba

“…Although this relationship needs further clarification; these strong correlations with major cations may suggest the relevant role of Mg in metabolic pathways (as relevant as the synthesis of bacteriochlorophyll; Boldareva-Nuianzina et al, 2013 ). The contrasting N:Ca correlation of OTUs, mostly positive for Bacteroidetes but negative for Proteobacteria (Table S4 ), may be an indication of profound differences between these groups such as in reproductive strategies, resource utilization (Taylor et al, 2013 ), diazotrophic potential (Alcántara-Hernández et al, 2017 ) and overall niche specialization. Actually, in some cases, synergistic associations have been proposed for these microbes (particularly between Flavobacterales and Rhodobacterales in phytoplankton blooms; Buchan et al, 2014 ).…”

“…Also clostridial genera have been reported to harbor a NADH- dependent nirB type nitrite reductase. Cyanobacterial nifH assigned to Nostocales and Oscillatoriales cyanobacteria as well as Alpha and Gammaproteobacteria (from different microbialite locations including Alchichica, Cuatro Ciénegas and Muyil) are described in Beltrán et al ( 2012 ) as well as Clostridiales and Deltaproteobacteria phylotypes (Alcántara-Hernández et al, 2017 ) in Alchichica microbialites.…”

“…A metagenomic exploration over two locations of Cuatro Ciénegas Basin (same pond of our PAI microbialite) showed microbialites were enriched in genes for phosphorus metabolism, establishment and development of biofilms and heterotrophic respiration (Breitbart et al, 2009 ). A vast genetic diversity for nitrogen (N) and phosphorus (P) cycling has been described for the microbialites from Alchichica soda lake (Beltrán et al, 2012 ; Valdespino-Castillo et al, 2014 , 2017 ; Alcántara-Hernández et al, 2017 ), where microbialites actively fix nitrogen (Beltrán et al, 2012 ). The geochemical characteristics (major cations) of microbialite ambient waters (Table 1 ) were compiled from different reference studies.…”

“…These studies have found that microbialites harbor a highly diverse microbial community fundamentally driven by environmental factors such as pH, conductivity and availability of nitrate (Centeno et al, 2012 ). Genomic surveys for some microbialites have revealed a broad potential for photoautotrophy and heterotrophic pathways involved in biogeochemical C, S, N, and P cycling (Beltrán et al, 2012 ; Valdespino-Castillo et al, 2014 , 2017 ; Cerqueda-García and Falcón, 2016 ; Saghaï et al, 2016 ; Alcántara-Hernández et al, 2017 ); and synthesis of enzyme cofactors, amino acids, production and degradation of extracellular polymeric substances (EPS) (Breitbart et al, 2009 ; Myshrall et al, 2010 ; Mobberley et al, 2013 ; White et al, 2015 ; Cerqueda-García and Falcón, 2016 ). Microbialite extracellular polymeric substances provide an adequate environment for binding transition metals to organic ligands (Geesey et al, 1988 ; Sforna et al, 2017 ) that may be microbe-dependent (Micheletti et al, 2008 ) and needs further exploration.…”