Lipid analysis was used to clarify the taxonomy of sulfate-reducing bacteria (SRB) to determine the composition of sulfate-reducing sedimentary communities. The phospholipid fatty acid composition of Desulfovibrio desulfuricans, Desulfotomaculum orientis, Desulfotomaculum nigrificans, and four SRB isolated from salt marsh sediment were determined by capillary gas-liquid chromatography and mass fragmentography. The fatty acid compositions of the SRB were compared using multivariate statistics and contrasted to the fatty acid compositions of Bacillus subtilus, Clostridium butyricum, Esherichia coli, Pseudomonas putida, Moraxella, sp. and Athrobacter sp. All SRB examined contained predominantly iso and anteiso methyl branched acids. Desulfovibrio desulfuricans, Desulfotomaculum orientis and Desulfotomaculum nigrificans contained high proportions of an uncommon 17 carbon iso monounsaturated acid. The major differences in fatty acid compositions among SRB were quantitative while the major differences between SRB and the other bacteria examined were qualitative. The fatty acid composition of Bacillus subtilus was most similar to those of the SRB in that it contained high proportions of branched saturated and monounsaturated acids. Esherichia coli and Clostridium butyricum were characterized by high proportions of 16 and 18 carbon saturated straight chained acids and 17 and 19 carbon cyclopropane acids. Pseudomonas putida and Moraxella sp. contained high proportions of 16 and 18 carbon monounsaturated acids. The fatty acid composition of Arthrobacter sp. was quite simple in that 90% of the acids was an iso methyl branched 15 carbon acid. / The phospholipid fatty acid composition of the microbial communities of freshwater and estuarine sediments were determined by analogous methods. The freshwater sediments were characterized by phospholipid concentrations which were 100 times higher than estuarine sediments and by high proportions of straight-chained saturated acids. The estuarine sediments contained higher proportions of branched and monounsaturated acids. The lipid content of all sediments generally decreased with depth and iso and anteiso branched acids became more abundant. Estuarine sediments taken from three locations along a 10 meter transect through a salt marsh were shown to vary 10 fold in lipid content and by a factor of 1000 in rates of sulfate respirations. Differences in microbial communities were demonstrated by their phospholipid fatty acid compositions and by their metabolism of carbon-14 labeled substrates. / Source: Dissertation Abstracts International, Volume: 45-09, Section: B, page: 2817. / Thesis (Ph.D.)--The Florida State University, 1984.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_75416 |
| Contributors | FREDRICKSON, HERBERT LOWRY., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 144 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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