AglB, catalyzing the oligosaccharyl transferase step of the archaeal N-glycosylation process, is essential in the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius

Microbiologyopen. 2014 Aug;3(4):531-43. doi: 10.1002/mbo3.185. Epub 2014 Jun 10.


Sulfolobus acidocaldarius, a thermo-acidophilic crenarchaeon which grows optimally at 76 °C and pH 3, exhibits an astonishing high number of N-glycans linked to the surface (S-) layer proteins. The S-layer proteins as well as other surface-exposed proteins are modified via N-glycosylation, in which the oligosaccharyl transferase AglB catalyzes the final step of the transfer of the glycan tree to the nascent protein. In this study, we demonstrated that AglB is essential for the viability of S. acidocaldarius. Different deletion approaches, that is, markerless in-frame deletion as well as a marker insertion were unsuccessful to create an aglB deletion mutant. Only the integration of a second aglB gene copy allowed the successful deletion of the original aglB.

Keywords: AglB; Archaea; Crenarchaeota; N-glycosylation; Sulfolobus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Genes, Archaeal
  • Genes, Essential*
  • Glycosylation
  • Hexosyltransferases / genetics*
  • Hexosyltransferases / metabolism*
  • Hydrogen-Ion Concentration
  • Membrane Glycoproteins / metabolism*
  • Membrane Proteins / genetics*
  • Membrane Proteins / metabolism*
  • Microbial Viability
  • Sulfolobus acidocaldarius / enzymology*
  • Sulfolobus acidocaldarius / genetics
  • Sulfolobus acidocaldarius / growth & development
  • Sulfolobus acidocaldarius / physiology*
  • Temperature


  • Membrane Glycoproteins
  • Membrane Proteins
  • S-layer proteins
  • Hexosyltransferases
  • dolichyl-diphosphooligosaccharide - protein glycotransferase