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Lipp, J. S.

Publications and source records attributed to Lipp, J. S..

3 recordsLinked to original sources

Novel Extended Tetraether Lipids Found in a High-CO2 Geyser

The growing research into the archaeal lipidome has uncovered a remarkable structural diversity in glycerol dialkyl glycerol tetraethers (GDGTs) and revealed complex membrane adaptations, especially in extreme environments. We performed a comprehensive analysis of the lipidome from the subsurface water of a CO2-rich, cold-water Geyser Andernach (Germany), using ultra-high-resolution mass spectrometry methods. We detected GDGT-0, presumably derived from the dominant community member Candidatus Altiarchaeum, providing evidence for its ability to synthesize tetraethers as previously predicted from metagenomic data. Beyond the typical GDGT-0 and acyclic glycerol trialkyl glycerol tetraether (GTGT-0), we discovered novel structural analogues, here referred to as extended GDGTs and GTGTs, characterized by the asymmetrical addition of up to two isoprenoid units to only one of their hydrocarbon side chains, analogous to those found in extended archaeols. The lack of GDGT ring synthase A (GrsA) and GrsB homologs in the corresponding metagenome-assembled genome, suggests that the producing archaeon may utilize extended GDGTs as a membrane adaptation to cope with the energy-depleted conditions of the geyser environment, highlighting the adaptive flexibility of archaea to extreme physicochemical conditions.

biochemistry↗

Unravelling Plankton Adaptation in Global Oceans through the Analysis of Lipidomes

A recent global survey of planktonic lipids showed a fundamental temperature-mediated regulation of lipid unsaturation in the global oceans [Holm H, et al. (2022) Science 376:1487-1491]. We expand the analysis of this dataset, both spatially and methodologically, to examine diverse environmental stressors across the ocean. Utilizing weighted correlation network analysis, we analyzed 3,164 lipid features in the dataset comprising 930 samples of suspended particulate matter, taken across a broad range of oceanographic conditions and water depths up to 600 meters. A total of 16 lipid clusters being co-expressed across diverse environments were identified. This analysis reveals universal relationships between environmental factors and the lipidome of the planktonic community. The largest lipid cluster, comprising 481 lipid features, including glycerolipids with polyunsaturated fatty acids, exhibited a significant enrichment in polar oceans, suggesting the highest lipid diversity in these ocean regions. Remarkably, marine plankton in these regions employ both desaturation and chain shortening for cold acclimation. Additionally, one lipid cluster strongly linked to the plankton residing in the surface of tropical and subtropical oceans was enriched with non-phosphorus lipids. We suggest this adaptive response enables the plankton to cope with phosphorous scarcity and heat stress. Notably, in the subsurface of these regions, a co-expressed cluster of highly unsaturated lipids is consistent with an enhanced production of polyunsaturated fatty acids by phytoplankton, possibly for low light adaptation. This adaptation is important as it may represent a source of essential fatty acids below the warm sea surface where such vital compounds may be diminished in the warmer future. SignificanceMarine plankton is vital for marine ecosystems and climate regulation. We analyzed a large lipidomics dataset of 930 samples collected from global oceans. This allowed us to explore how plankton adapt their lipidomes across different environments. Our findings show distinct lipid clusters correlating with specific environmental conditions, revealing mechanisms like chain shortening to cope with cold stress, enrichment of non-phosphorus lipids in tropical surface waters, and increased polyunsaturated fatty acids in low-light tropical subsurface areas. These adaptations are crucial for understanding how climate change will impact marine ecosystems.

microbiology↗

The exploration of Thermococcus barophilus lipidome reveals the widest variety of phosphoglycolipids in Thermococcales.

One of the most distinctive characteristics of Archaea is their unique lipids. While the general nature of archaeal lipids has been linked to their tolerance to extreme conditions, little is known about the diversity of lipidic structures Archaea are able to synthesize, which hinders the elucidation of the physicochemical properties of their cell membrane. In an effort to widen the known lipid repertoire of the piezophilic and hyperthermophilic model archaeon Thermococcus barophilus, we comprehensively characterized its intact polar lipid (IPL), core lipid (CL), and polar head group compositions using a combination of cutting-edge liquid chromatography and mass spectrometric ionization systems. We tentatively identified 82 different IPLs based on five distinct CLs and 10 polar head group derivatives of phosphatidylhexoses, including compounds reported here for the first time, e.g., di-N-acetylhexosamine phosphatidylhexose-bearing lipids. Despite having extended the knowledge on the lipidome, our results also indicate that the majority of T. barophilus lipids remain inaccessible to current analytical procedures and that improvements in lipid extraction and analysis are still required. This expanded yet incomplete lipidome nonetheless opens new avenues for understanding the physiology, physicochemical properties, and organization of the membrane in this archaeon as well as other Archaea.

microbiology↗