Microbial mat enrichment cultures
Microbial diversity of the microbial mat from Laguna Tebenquiche was investigated using 16S rRNA amplicon sequencing. Samples of the microbial mat (n=12) were cultivated under different P and NaCl concentrations under high arsenate. Enrichment cultures were obtained in 250 mL Erlenmeyer flasks with 60 mL of Chemically Defined Medium (CDM) was supplemented with 25 mM sodium arsenate and inoculated with 5 g of a microbial mat from the Laguna Tebenquiche. To analyze which taxa are selected in phosphate deficiency, the CDM medium was modified from its original composition using 0 and 1 mM of K2HPO4 as the unique source of phosphate. Both phosphate conditions were repeated using CDM medium supplemented with 15% and 25% of NaCl to emulate the high salinity (NaCl) concentrations of High Altitude Andean Lakes (HAALs)