Protein glycosylation in Archaea: Sweet and extreme

Abstract

While each of the three domains of life on Earth possesses unique traits and relies on characteristic biological strategies, some processes are common to Eukarya, Bacteria and Archaea. Once believed to be restricted to Eukarya, it is now clear that Bacteria and Archaea are also capable of performing N-glycosylation. However, in contrast to Bacteria, where this posttranslational modification is still considered a rare event, numerous species of Archaea, isolated from a wide range of environments, have been reported to contain proteins bearing Asn-linked glycan moieties. Analysis of the chemical composition of the Asn-linked polysaccharides decorating archaeal proteins has, moreover, revealed the use of a wider variety of sugar subunits than seen in either eukaryal or bacterial glycoproteins. Still, although first reported some 30 years ago, little had been known of the steps or components involved in the archaeal version of this universal posttranslational modification. Now, with the availability of sufficient numbers of genome sequences and the development of appropriate experimental tools, molecular analysis of archaeal N-glycosylation pathways has become possible. Accordingly using halophilic, methanogenic and thermophilic model species, insight into the biosynthesis and attachment of N-linked glycans decorating archaeal glycoproteins is starting to amass. In this review, current understanding of N-glycosylation in Archaea is described.

Conservation of the PTEN catalytic motif in the bacterial undecaprenyl pyrophosphate phosphatase, BacA/UppP

“…eukaryotes, bacteria and archaea (Calo et al, 2010;Helenius & Aebi, 2004;Jones et al, 2009;Larkin & Imperiali, 2011;Nothaft & Szymanski, 2010;Schwarz & Aebi, 2011;Weerapana & Imperiali, 2006). Monophosphate lipid carriers are also used in the synthesis of bacterial cell envelope polymers such as peptidoglycan, lipopolysaccharides and teichoic acids (Bouhss et al, 2008;Cantagrel & Lefeber, 2011;de Kruijff et al, 2008;Lovering et al, 2012;Reusch & Salton, 1984;Swoboda et al, 2010).…”

Mixed disulfide formation in vitro between a glycoprotein substrate and yeast oligosaccharyltransferase subunits Ost3p and Ost6p

“…Asparagine (N-)linked glycosylation is a common co-and post-translational modification that affects the structure and function of secretory and membrane bound proteins in eukaryotes [1], archaea [2] and some bacteria [3]. In eukaryotes, nascent polypeptide is N-glycosylated by the enzyme oligosaccharyltransferase (OTase) after entry into the endoplasmic reticulum (ER) lumen through the translocon [4,5,6].…”

Polypeptide binding specificities of Saccharomyces cerevisiae oligosaccharyltransferase accessory proteins Ost3p and Ost6p

“…[1][2][3] N-glycosylation is catalyzed in the lumen of the endoplasmic reticulum (ER) by the multiprotein complex oligosaccharyltransferase (OTase). 4 OTase physically associates with ribosomes bound at the translocon 5 and transfers an oligosaccharide (typically Glucose 3 Mannose 9 N-acetylglucosamine 2 ) from a dolicholpyrophosphate donor to selected Asn side-chains in nascent polypeptide substrates.…”