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Characterization of the halophilic archaeal community in saltern crystallizer ponds by means of polar lipid analysis 总被引：1，自引：0，他引：1
Aharon Oren 《International Journal of Salt Lake Research》1994,3(1):15-29
Saltern crystallizer ponds are coloured red due to the presence of dense communities of red halophilic archaea (family Halobacteriaceae). Little quantitative information exists on the species distribution within the archaeal community in such ponds. As the different genera of the Halobacteriaceae differ in polar lipid content, and especially in the types of glycolipids, lipid analysis can be used to obtain information on the nature of the organisms present. Analysis of the polar lipids extracted from the biomass collected from the saltern crystallizer ponds in Eilat, Israel, showed one major glycolipid to be present, co-chromatographing with the sulfated diglycosyl diether lipid characteristic of the genusHaloferax. No indications were found for the presence of significant amounts of those glycolipids that would indicate the presence of large numbers of other archaea such asHalobacterium species (H. cutirubrum andH. salinarium, characterized by sulfated triglycosyl and tetraglycosyl diethers), orHaloarcula species (possessing a triglycosyl diether). Phosphatidyl glycerosulfate, a polar lipid absent inHaloferax species, was present in the lipid extract from the crystallizer ponds, suggesting that the dominant microorganism present may be related to strains which are presently classified in the genusHalobacterium but are awaiting a taxonomic reappraisal (H. sodomense, H. saccharovorum, andH. trapanicum). Organisms of the latter group are characterized by sulfated diglycosyl diethers, and the presence of phosphatidyl glycerosulfate. Attempts to isolate the dominant type of bacterium on agar plates yielded relatively low counts (1–2 orders of magnitude lower than the numbers observed microscopically) of bacteria, and most of the isolates had a polar lipid composition characteristic of theH. salinarium group or theH. sodomense-H. saccharovorum-H. trapanicum group. 相似文献
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Heterocystous cyanobacteria are important diazotrophs commonly found in freshwater and ocean. They can produce special glycolipids known as Heterocyst Glycolipids (HGs) in their inner membrane layer. HGs are typically long-chain diols, triols, or hydroxyketones connected with a sugar moiety. HGs are unique biomarkers of heterocystous cyanobactria, which are relative stable and can be detected in lakes, marine systems, microbial mats and sediments. The study of HGs in biogeochemistry has not been carried out until recent years. HGs are proved to have great potential in indicating heterocystous cyanbacteria community and environment conditions. In this paper, the mechanism of cyanobacterial heterocyst differentiation and structure of HGs were introduced. In particular, emphasis was put on the application of HGs to infer environmental temperature, heterocystous cyanobacteria community, terrestrial organic input and nitrogen fixationin. The prospect of future study was also proposed. 相似文献
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Marine endosymbiotic heterocystous cyanobacteria make unique heterocyst glycolipids (HGs) containing pentose (C5) moieties. Functionally similar HGs with hexose (C6) moieties found in free-living cyanobacteria occur in the sedimentary record, but C5 HGs have not been documented in the natural environment. Here we developed a high performance liquid chromatography multiple reaction monitoring (MRM) mass spectrometry (HPLC–MS2) method specific for trace analysis of long chain C5 HGs and applied it to cultures of Rhizosolenia clevei Ostenfeld and its symbiont Richelia intracellularis which were found to contain C5 HGs and no C6 HGs. The method was then applied to suspended particulate matter (SPM) and surface sediment from the Amazon plume region known to harbor marine diatoms carrying heterocystous cyanobacteria as endosymbionts. C5 HGs were detected in both marine SPM and surface sediments, but not in SPM or surface sediment from freshwater settings in the Amazon basin. Rather, the latter contained C6 HGs, established biomarkers for free-living heterocystous cyanobacteria. Our results indicate that the C5 HGs may be potential biomarkers for marine endosymbiotic heterocystous cyanobacteria. 相似文献
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