A predicted geranylgeranyl reductase reduces the ω-position isoprene of dolichol phosphate in the halophilic archaeon, Haloferax volcanii.

Journal Article (Journal Article)

In N-glycosylation in both Eukarya and Archaea, N-linked oligosaccharides are assembled on dolichol phosphate prior to transfer of the glycan to the protein target. However, whereas only the α-position isoprene subunit is saturated in eukaryal dolichol phosphate, both the α- and ω-position isoprene subunits are reduced in the archaeal lipid. The agents responsible for dolichol phosphate saturation remain largely unknown. The present study sought to identify dolichol phosphate reductases in the halophilic archaeon, Haloferax volcanii. Homology-based searches recognize HVO_1799 as a geranylgeranyl reductase. Mass spectrometry revealed that cells deleted of HVO_1799 fail to fully reduce the isoprene chains of H. volcanii membrane phospholipids and glycolipids. Likewise, the absence of HVO_1799 led to a loss of saturation of the ω-position isoprene subunit of C(55) and C(60) dolichol phosphate, with the effect of HVO_1799 deletion being more pronounced with C(60) dolichol phosphate than with C(55) dolichol phosphate. Glycosylation of dolichol phosphate in the deletion strain occurred preferentially on that version of the lipid saturated at both the α- and ω-position isoprene subunits.

Full Text

Duke Authors

Cited Authors

  • Naparstek, S; Guan, Z; Eichler, J

Published Date

  • June 2012

Published In

Volume / Issue

  • 1821 / 6

Start / End Page

  • 923 - 933

PubMed ID

  • 22469971

Pubmed Central ID

  • PMC3340491

International Standard Serial Number (ISSN)

  • 0006-3002

Digital Object Identifier (DOI)

  • 10.1016/j.bbalip.2012.03.002


  • eng

Conference Location

  • Netherlands