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Abstract Glycerol dibiphytanyl glycerol tetraethers (GDGTs) are archaeal monolayer membrane lipids that can provide a competitive advantage in extreme environments. Here, we identify a radical SAM protein, tetraether synthase (Tes), that participates in the synthesis of GDGTs. Attempts to generate a tes-deleted mutant in Sulfolobus acidocaldarius were unsuccessful, suggesting that the gene is essential in this organism. Heterologous expression of tes homologues leads to production of GDGT and structurally related lipids in the methanogen Methanococcus maripaludis (which otherwise does not synthesize GDGTs and lacks a tes homolog, but produces a putative GDGT precursor, archaeol). Tes homologues are encoded in the genomes of many archaea, as well as in some bacteria, in which they might be involved in the synthesis of bacterial branched glycerol dialkyl glycerol tetraethers.
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This content will become publicly available on May 1, 2026
Total Synthesis of the Membrane Spanning Tetraether Lipid brGDGT Ia and Elucidation of Its Stereochemical Configuration
Abstract Glycerol dialkyl glycerol tetraethers (GDGTs) are a group of membrane spanning lipids produced by both Archaea and Bacteria. Branched GDGTs (brGDGTs) are a class of these tetraether lipids known to be produced by certain bacteria and are commonly found in terrestrial environments. Due to their environmental ubiquity, high preservation potential, and role in membrane adaptation, brGDGTs form the basis of many widely employed paleoenvironmental proxies. The tetramethylated brGDGT Ia is the most commonly reported branched tetraether in culturedAcidobacteriaand is a key component of brGDGT‐based temperature indices. Herein, we report the first total synthesis of brGDGT Ia, thereby elucidating the relative configuration of the methyl branches as syn. We further demonstrate that VCD spectroscopy is a suitable tool to determine the absolute configuration of these cryptochiral compounds, a method waiting to be applied to the natural lipid, but currently hampered by its limited availability.
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- Award ID(s):
- 1945484
- PAR ID:
- 10588677
- Publisher / Repository:
- Chemistry - A European Journal
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 31
- Issue:
- 25
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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