Identification of AglE, a second glycosyltransferase involved in N glycosylation of the Haloferax volcanii S-layer glycoprotein.
Archaea, like Eukarya and Bacteria, are able to N glycosylate select protein targets. However, in contrast to relatively advanced understanding of the eukaryal N glycosylation process and the information being amassed on the bacterial process, little is known of this posttranslational modification in Archaea. Toward remedying this situation, the present report continues ongoing efforts to identify components involved in the N glycosylation of the Haloferax volcanii S-layer glycoprotein. By combining gene deletion together with mass spectrometry, AglE, originally identified as a homologue of murine Dpm1, was shown to play a role in the addition of the 190-Da sugar subunit of the novel pentasaccharide decorating the S-layer glycoprotein. Topological analysis of an AglE-based chimeric reporter assigns AglE as an integral membrane protein, with its N terminus and putative active site facing the cytoplasm. These finding, therefore, contribute to the developing picture of the N glycosylation pathway in Archaea.
Abu-Qarn
Mehtap
M
Department of Life Sciences, Ben Gurion University, P.O. Box 653, Beersheva 84105, Israel.
Giordano
Assunta
A
Battaglia
Francesca
F
Trauner
Andrej
A
Hitchen
Paul G
PG
Morris
Howard R
HR
Dell
Anne
A
Eichler
Jerry
J
D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism*; D002874:Chromosome Mapping; D017353:Gene Deletion; D006031:Glycosylation; D019622:Haloferax volcanii / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D008364:Mannosyltransferases / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D019843:Archaeal Proteins; D008562:Membrane Glycoproteins; D008364:Mannosyltransferases; C022755:dolichyl-phosphate beta-D-mannosyltransferase