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Microorganismos en el hielo acumulado del lago Vostok, en la Antártida
D M Karl1, D F Bird, K Björkman
1School of Ocean and Earth Science and Technology (SOEST), University of Hawaii, Honolulu, HI 96822, USA.
Science (New York, N.Y.)
|December 11, 1999
Resumen
La vida microbiana puede existir en el Lago Vostok subglacial de la Antártida. El análisis del hielo acumulado reveló bacterias viables, lo que sugiere que este entorno único podría albergar microorganismos a pesar de los bajos niveles de nutrientes.
Área de la Ciencia:
- Microbiología Microbiología.
- Limología Limología.
- Glaciología glaciología.
Sus antecedentes:
- El lago Vostok es un lago subglacial antártico cubierto por aproximadamente 4 kilómetros de hielo.
- El hielo acumulado del núcleo de hielo Vostok 5G proporciona una muestra de este entorno subglacial único.
Objetivo del estudio:
- Para investigar la presencia y viabilidad de microorganismos en el hielo acumulado del lago Vostok.
- Para caracterizar la comunidad microbiana y las condiciones nutricionales dentro de este ecosistema subglacial.
Principales métodos:
- Enumeración de células bacterianas mediante el uso de microscopía.
- Detección de lipopolisacáridos (biomarcadores bacterianos Gram negativos).
- Evaluación de la viabilidad microbiana a través de ensayos de respiración en el sustrato (carbono-14 etiquetado con acetato y glucosa).
Principales resultados:
- Las densidades de células bacterianas oscilaron entre 2 x 10^2 y 3 x 10^2 células por mililitro.
- Se detectaron bajas concentraciones de nutrientes para el crecimiento.
- La presencia de lipopolisacáridos indicó un predominio de las bacterias gramnegativas.
- La respiración microbiana confirmó la viabilidad de al menos una parte del conjunto microbiano.
Conclusiones:
- El hielo acumulado del lago Vostok contiene microorganismos viables.
- El lago Vostok puede albergar un ecosistema microbiano único capaz de sostener la vida en condiciones extremas.
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