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Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria
Published on: July 24, 2016
La evidencia de la fotosíntesis anoxigénica proviene de la distribución de bacterioclorófilos en el Mar Negro
D J Repeta1, D J Simpson, B B Jorgensen
1Department of Chemistry, Woods Hole Oceanographic Institution, Massachusetts 02543, USA.
Nature
|November 2, 1989
Resumen
La fotosíntesis anoxigénica, impulsada por bacterias específicas, es un contribuyente significativo al Mar Negro.
Área de la Ciencia:
- Biología Marina Biología Marina.
- Biogeoquímica La biogeoquímica es la bioquímica.
- Ecología microbiana Ecología microbiana.
Sus antecedentes:
- El Mar Negro es la cuenca marina anóxica más grande del mundo.
- La fotosíntesis anoxigenada en aguas profundas es un tema muy debatido.
- La penetración de la luz en aguas ricas en sulfuro puede apoyar la producción primaria anaeróbica.
Objetivo del estudio:
- Para investigar el papel de la fotosíntesis anoxigenada en el ciclo del carbono del Mar Negro.
- Para analizar los pigmentos fotosintéticos en la columna de agua del Mar Negro.
- Para identificar los tipos de bacterias fotosintéticas presentes.
Principales métodos:
- Análisis de pigmentos fotosintéticos en las partículas en suspensión.
- Muestreo en dos estaciones en la cuenca occidental del Mar Negro.
- Identificación y cuantificación del pigmento.
Principales resultados:
- Se encontraron altas concentraciones de bacterioclorofila en la quimioclina.
- Los pigmentos indican la presencia de Chlorobium phaeobacteroides y C. phaeovibriodes.
- Los niveles de bacterioclorofila excedieron los niveles de clorofila-a en las aguas superiores en una estación.
Conclusiones:
- La fotosíntesis anoxigenada es un componente importante de la producción primaria en el Mar Negro.
- El fenómeno puede ser reciente, relacionado con una quimioclina superficial.
- Se identificaron carotenoides aromáticos específicos y bacterioclorófilos-e.
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