Bioenergetic studies of sulfur reduction in the hyperthermophilic archaebacteria Pyrodictium brockii and Pyrococcus furiosus
The central focus of this work was the investigation of the central energy generating pathways of two hyperthermophilic sulfidogenic archaebacteria, Pyrodictium brockii and Pyrococcus furiosus. A potential application of these organisms in the desulfurization of coals was investigated. An effective ;means of removing elemental sulfur (S[degrees]) was developed. Analytical and processing applications are discussed. The rates of sulfur removal by the hyperthermophiles were 5 fold those measured of the mesophile, Thiobacillus thiooxidans. The primary energy generating pathway of Pyrodicutium brockii has been termed hydrogen-sulfur autotrophy and is characterized by the oxidation of H[sub 2] and reduction of S[degrees]. The goals of this part of the work were to quantify the stoichiometry of this organism and to estimate Y[sub s[sup MAX]] and m[sub s] for Pyrodicutium brockii, with S[degrees] as the energy-limiting substrate. Unfortunately, due to problems with culture stability only very limited data were collected and therefore, only preliminary estimates could be made. The metabolism of Pyrococcus furiosus was studied using maltose as the energy-limiting carbon source. Continuous culture experiments in the presence and absence of S[degrees] were performed. The maintenance coefficients, m[sub x], were found to be almost identical with or without S[degrees] suggesting that it has little to do with energy dissipating functions in Pyrococcus furiosus. The magnitude of the m[sub s] 's, in terms of glucose equivalents, were fairly high when compared to those estimated for mesophilic microorganisms. The maximal yield coefficients, Y[sub s[sup MAX]], were found to be significantly different, 99 g cdw[sup 1]/mole maltose with S[degrees] and 51 g cdw/mole maltose without S[degrees].
- Research Organization:
- Johns Hopkins Univ., Baltimore, MD (United States)
- OSTI ID:
- 5088725
- Resource Relation:
- Other Information: Thesis (Ph.D.)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii. Progress report
Analysis of thermally-stable electron transport factors from the hyperthermophilic archaebacterium Pyrodictium brockii