Distinct Regions of the Haloferax volcanii Dolichol Phosphate-Mannose Synthase AglD Mediate the Assembly and Subsequent Processing of the Lipid-Linked Mannose.

Journal Article (Journal Article)

Haloferax volcanii AglD is currently the only archaeal dolichol phosphate (DolP)-mannose synthase shown to participate in N-glycosylation. However, the relation between AglD and Pyrococcus furiosus PF0058, the only archaeal DolP-mannose synthase for which structural information is presently available, was unclear. In this report, similarities between the PF0058 and AglD catalytic domains were revealed. At the same time, AglD includes a transmembrane domain far longer than that of PF0058 or other DolP-mannose synthases. To determine whether this extension affords AglD functions in addition to generating mannose-charged DolP, a series of Hfx. volcanii strains expressing truncated versions of AglD was generated. Mass spectrometry revealed that a version of AglD comprising the catalytic domain and only two of the six to nine predicted membrane-spanning domains could mediate mannose addition to DolP. However, in cells expressing this or other truncated versions of AglD, mannose was not transferred from the lipid to the protein-bound tetrasaccharide precursor of the N-linked pentasaccharide normally decorating Hfx. volcanii glycoproteins. These results thus point to AglD as contributing to additional aspects of Hfx. volcanii N-glycosylation beyond charging DolP with mannose. Accordingly, the possibility that AglD, possibly in coordination with AglR, translocates DolP-mannose across the plasma membrane is discussed.

Full Text

Duke Authors

Cited Authors

  • Zaretsky, M; Guan, Z; Zarivach, R; Eichler, J

Published Date

  • January 2022

Published In

Volume / Issue

  • 204 / 1

Start / End Page

  • e0044721 -

PubMed ID

  • 34633871

Pubmed Central ID

  • PMC8780517

Electronic International Standard Serial Number (EISSN)

  • 1098-5530

International Standard Serial Number (ISSN)

  • 0021-9193

Digital Object Identifier (DOI)

  • 10.1128/jb.00447-21

Language

  • eng