Characterization of Ten Heterotetrameric NDP-Dependent Acyl-CoA Synthetases of the Hyperthermophilic Archaeon Pyrococcus furiosus
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
The hyperthermophilic archaeon Pyrococcus furiosus grows by fermenting peptides and carbohydrates to organic acids. In the terminal step, acyl-CoA synthetase (ACS) isoenzymes convert acyl-CoA derivatives to the corresponding acid and conserve energy in the form of ATP. ACS1 and ACS2 were previously purified from P. furiosus and have structures but the genome contains genes encoding three additional -subunits. The ten possible combinations of and genes were expressed in E. coli and each resulted in stable and active isoenzymes. The -subunit of each isoenzyme determined CoA-based substrate specificity and between them they accounted for the CoA derivatives of fourteen amino acids. The -subunit determined preference for adenine or guanine nucleotides. The GTP-generating isoenzymes are proposed to play a role in gluconeogenesis by producing GTP for GTP-dependent phosphoenolpyruvate carboxykinase and for other GTP-dependent processes. Transcriptional and proteomic data showed that all ten isoenzymes are constitutively expressed indicating that both ATP and GTP are generated from the metabolism of most of the amino acids. A phylogenetic analysis showed that the ACSs of P. furiosus and other members of the Thermococcales are evolutionarily distinct from those found throughout the rest of biology, including those of other hyperthermophilic archaea.
- Research Organization:
- Univ. of Georgia, Athens, GA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- Grant/Contract Number:
- FG05-95ER20175
- OSTI ID:
- 1197842
- Alternate ID(s):
- OSTI ID: 1626217
- Journal Information:
- Archaea, Journal Name: Archaea Vol. 2014; ISSN 1472-3646
- Publisher:
- Hindawi Publishing CorporationCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
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