Abstracto

Physiology and growth of Pyrococcus sp. HT3 in bach culture with cellobiose and maltose as the principal carbon sources

Mouloud Kecha, Said Benallaoua, Francis Duchiron

The hydrothermal hot spring archaeonPyrococcussp. T3 was grown in batch cultures in closed bottles, both in the presence and in the absence of elemental sulfur. Growth on carbohydrates, proteinaceous substrates and amino acids was investigated. The disaccharides maltose and cellobiose were shown not to be able to enhance growth suggesting that Pyrococcussp. T3 is unable to use them as sole carbon sources. By contrast, proteinaceous substrates such as peptone and brain heart infusion were shown to be very good substrates for the growth of Pyrococcussp. T3. Growth on brain heart infusion was shown to require additional nutrients when sulfur was not present in the culture medium. Growth on amino acids only took place in the presence of sulfur. These results indicate that sulfur plays an important role in the metabolism and energetics of Pyrococcussp. HT3.