Tetraether archaeal lipids promote long‐term survival in extreme conditions
- Department of Biochemistry and Molecular Biology Colorado State University Fort Collins Colorado USA
- Department of Earth System Science Stanford University Stanford California USA
- Cell and Molecular Biology Graduate Program Colorado State University Fort Collins Colorado USA
- Department of Chemistry Stanford University Stanford California USA
- Department of Biochemistry and Molecular Biology Colorado State University Fort Collins Colorado USA, Cell and Molecular Biology Graduate Program Colorado State University Fort Collins Colorado USA
The sole unifying feature of the incredibly diverse Archaea is their isoprenoid‐based ether‐linked lipid membranes. Unique lipid membrane composition, including an abundance of membrane‐spanning tetraether lipids, impart resistance to extreme conditions. Many questions remain, however, regarding the synthesis and modification of tetraether lipids and how dynamic changes to archaeal lipid membrane composition support hyperthermophily. Tetraether membranes, termed glycerol dibiphytanyl glycerol tetraethers (GDGTs), are generated by tetraether synthase (Tes) by joining the tails of two bilayer lipids known as archaeol. GDGTs are often further specialized through the addition of cyclopentane rings by GDGT ring synthase (Grs). A positive correlation between relative GDGT abundance and entry into stationary phase growth has been observed, but the physiological impact of inhibiting GDGT synthesis has not previously been reported. Here, we demonstrate that the model hyperthermophile Thermococcus kodakarensis remains viable when Tes (TK2145) or Grs (TK0167) are deleted, permitting phenotypic and lipid analyses at different temperatures. The absence of cyclopentane rings in GDGTs does not impact growth in T. kodakarensis , but an overabundance of rings due to ectopic Grs expression is highly fitness negative at supra‐optimal temperatures. In contrast, deletion of Tes resulted in the loss of all GDGTs, cyclization of archaeol, and loss of viability upon transition to the stationary phase in this model archaea. These results demonstrate the critical roles of highly specialized, dynamic, isoprenoid‐based lipid membranes for archaeal survival at high temperatures.
- Research Organization:
- Colorado State Univ., Fort Collins, CO (United States)
- Sponsoring Organization:
- USDOE; USDOE Office of Science (SC)
- Grant/Contract Number:
- SC0014597
- OSTI ID:
- 2308880
- Alternate ID(s):
- OSTI ID: 2350741
OSTI ID: 2579910
- Journal Information:
- Molecular Microbiology, Journal Name: Molecular Microbiology Journal Issue: 5 Vol. 121; ISSN 0950-382X
- Publisher:
- Wiley-BlackwellCopyright Statement
- Country of Publication:
- FAO
- Language:
- English