Biodiversity analyses of Laguna Catal, an Andean High Altitude wetland (4,000 masl).

OMAR ORDOÑEZ, MARÍA R. FLORES, CRISTINA ESTEVEZ AND MARIA E. FARÍAS.

Rosario, Argentina

Congreso; V Congreso argentino de Microbiologia General; 2008

Sociedad Argentina de Microbiología General

Laguna (L.) Catal is a wetland of Salar del Hombre Muerto. It is placed at 4,000 masl in the Argentinean north western andean Puna desert (22°35’S and 66°55’W). This wetland is characterized by extreme environmental conditions as high salinity (160 ppm), sharp aridity, high ultraviolet radiation, significant extreme temperature daily, clear sky and constant winds. Thus, planktonic communities that live in this wetland are able to resist such severe environmental conditions. Aim: The aim of this work was to study the planktonic organisms biodiversity of water samples from L. Catal by molecular and microbiological techniques. Material and Methods: Salinity, water temperature, deep and ultraviolet-b radiation irradiance were measured <i>in situ</i>. Samples waters were fixed with formaldehyde 4% for DAPI bacterial count and zooplankton and phytoplankton microscopy analyses. Surface water samples were collected in sterile polyethylene bottles, after pre-rinsing the containers with wetland water. They were stored at 4ºC until further processing in the laboratory (within approximately 24 h after collection). Bacterioplankton community was analyzed by Denaturing Gradient Gel Electrophoresis (DGGE) and Fluorescents In Situ Hybridization (FISH). Isolated bacteria were identified by sequencing of 16S rDNA. Salinity, water temperature, deep and ultraviolet-b radiation irradiance were measured <i>in situ</i>. Samples waters were fixed with formaldehyde 4% for DAPI bacterial count and zooplankton and phytoplankton microscopy analyses. Surface water samples were collected in sterile polyethylene bottles, after pre-rinsing the containers with wetland water. They were stored at 4ºC until further processing in the laboratory (within approximately 24 h after collection). Bacterioplankton community was analyzed by Denaturing Gradient Gel Electrophoresis (DGGE) and Fluorescents In Situ Hybridization (FISH). Isolated bacteria were identified by sequencing of 16S rDNA. : Salinity, water temperature, deep and ultraviolet-b radiation irradiance were measured <i>in situ</i>. Samples waters were fixed with formaldehyde 4% for DAPI bacterial count and zooplankton and phytoplankton microscopy analyses. Surface water samples were collected in sterile polyethylene bottles, after pre-rinsing the containers with wetland water. They were stored at 4ºC until further processing in the laboratory (within approximately 24 h after collection). Bacterioplankton community was analyzed by Denaturing Gradient Gel Electrophoresis (DGGE) and Fluorescents In Situ Hybridization (FISH). Isolated bacteria were identified by sequencing of 16S rDNA. Results: Phytoplankton counts showed an abundance of between 100 and 220 (cells/ml) characterized by Bacillariophyceae (Diatoms), Cyanophyceae and Chlorophyceae. Zooplankton was represented by copepods with different distribution along the wetland. Bacteria diversity was related mainly to Gammaproeteobacterias group, Bacteroidetes and Halobacteria (ie, <i>Marinobacter </i>sp. <i>Halomonas</i>sp. and <i>Halobacillus</i> sp.). However, low similarity with bacteria previously described suggests that this environment has an abundance of new microorganisms for phylogeny. suggests that this environment has an abundance of new microorganisms for phylogeny. s</i> sp.). However, low similarity with bacteria previously described suggests that this environment has an abundance of new microorganisms for phylogeny.