title: Bacterial cell-envelope glycoconjugates.
abstract: Prokaryotic glycosylation fulfills an important role in maintaining and protecting the structural integrity and function of the bacterial cell wall, as well as serving as a flexible adaption mechanism to evade environmental and host-induced pressure. The scope of bacterial and archaeal protein glycosylation has considerably expanded over the past decade(s), with numerous examples covering the glycosylation of flagella, pili, glycosylated enzymes, as well as surface-layer proteins. This article addresses structure, analysis, function, genetic basis, biosynthesis, and biomedical and biotechnological applications of cell-envelope glycoconjugates, S-layer glycoprotein glycans, and "nonclassical" secondary-cell wall polysaccharides. The latter group of polymers mediates the important attachment and regular orientation of the S-layer to the cell wall. The structures of these glycopolymers reveal an enormous diversity, resembling the structural variability of bacterial lipopolysaccharides and capsular polysaccharides. While most examples are presented for Gram-positive bacteria, the S-layer glycan of the Gram-negative pathogen Tannerella forsythia is also discussed. In addition, archaeal S-layer glycoproteins are briefly summarized.
authors.affiliation: Department of NanoBiotechnology, NanoGlycobiology Unit, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: Paul
authors.initials: P
authors.lastname: Messner
authors.forename: Christina
authors.initials: C
authors.lastname: Schäffer
authors.forename: Paul
authors.initials: P
authors.lastname: Kosma
mesh_terms: D001419:Bacteria / Q000166:cytology*; D002240:Carbohydrate Sequence; D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism; D002473:Cell Wall / Q000737:chemistry* / Q000378:metabolism; D005818:Genetic Engineering; D006001:Glycoconjugates / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D011134:Polysaccharides / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism
chemical_list: D006001:Glycoconjugates; D006023:Glycoproteins; D011134:Polysaccharides
keywords: Archaea; Bacteria; Glycoprotein; Secondary cell-wall polymers; Surface layer