Primary structure and glycosylation of the S-layer protein of Haloferax volcanii.
The outer surface of the archaebacterium Haloferax volcanii (formerly named Halobacterium volcanii) is covered with a hexagonally packed surface (S) layer. The gene coding for the S-layer protein was cloned and sequenced. The mature polypeptide is composed of 794 amino acids and is preceded by a typical signal sequence of 34 amino acid residues. A highly hydrophobic stretch of 20 amino acids at the C-terminal end probably serves as a transmembrane domain. Clusters of threonine residues are located adjacent to this membrane anchor. The S-layer protein is a glycoprotein containing both N- and O-glycosidic bonds. Glucosyl-(1----2)-galactose disaccharides are linked to threonine residues. The primary structure and the glycosylation pattern of the S-layer glycoproteins from Haloferax volcanii and from Halobacterium halobium were compared and found to exhibit distinct differences, despite the fact that three-dimensional reconstructions from electron micrographs revealed no structural differences at least to the 2.5-nm level attained so far (M. Kessel, I. Wildhaber, S. Cohe, and W. Baumeister, EMBO J. 7:1549-1554, 1988).
Sumper
M
M
Lehrstuhl Biochemie I, Universität Regensburg, Federal Republic of Germany.
Berg
E
E
Mengele
R
R
Strobel
I
I
D000595:Amino Acid Sequence; D001105:Archaea / Q000032:analysis* / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D001426:Bacterial Proteins; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D006023:Glycoproteins / Q000235:genetics / Q000302:isolation & purification; D006031:Glycosylation; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000378:metabolism; D015183:Restriction Mapping; D012995:Solubility
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D011498:Protein Precursors; C055764:S-layer proteins