3VGP

Crystal structure of the C-terminal globular domain of oligosaccharyltransferase (AF_0329) from Archaeoglobus fulgidus

3VGP の概要

• エントリーDOI: 10.2210/pdb3vgp/pdb
• 分子名称: Transmembrane oligosaccharyl transferase, putative (2 entities in total)
• 機能のキーワード: glycosyltransferase, cell membrane, transferase
• 由来する生物種: Archaeoglobus fulgidus
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 19292.89

構造登録者

Matsumoto, S.,Igura, M.,Nyirenda, J.,Yuzawa, S.,Noda, N.N.,Inagaki, F.,Kohda, D. (登録日: 2011-08-18, 公開日: 2012-07-04, 最終更新日: 2024-10-30)

主引用文献

Matsumoto, S.,Igura, M.,Nyirenda, J.,Matsumoto, M.,Yuzawa, S.,Noda, N.N.,Inagaki, F.,Kohda, D.
Crystal Structure of the C-Terminal Globular Domain of Oligosaccharyltransferase from Archaeoglobus fulgidus at 1.75 A Resolution
Biochemistry, 51:4157-4166, 2012

PubMed Abstract: Protein N-glycosylation occurs in the three domains of life. Oligosaccharyltransferase (OST) transfers glycan to asparagine in the N-glycosylation sequon. The catalytic subunit of OST is called STT3 in eukaryotes, AglB in archaea, and PglB in eubacteria. The genome of a hyperthermophilic archaeon, Archaeoglobus fulgidus, encodes three AglB paralogs. Two of them are the shortest AglBs across all domains of life. We determined the crystal structure of the C-terminal globular domain of the smallest AglB to identify the minimal structural unit. The Archaeoglobus AglB lacked a β-barrel-like structure, which had been found in other AglB and PglB structures. In agreement, the deletion in a larger Pyrococcus AglB confirmed its dispensability for the activity. By contrast, the Archaeoglobus AglB contains a kinked helix bearing a conserved motif, called DK/MI motif. The lysine and isoleucine residues in the motif participate in the Ser/Thr recognition in the sequon. The Archaeoglobus AglB structure revealed that the kinked helix contained an unexpected insertion. A revised sequence alignment based on this finding identified a variant type of the DK motif with the insertion. A mutagenesis study of the Archaeoglobus AglB confirmed the contribution of this particular type of the DK motif to the activity. When taken together with our previous results, this study defined the classification of OST: one group consisting of eukaryotes and most archaea possesses the DK-type Ser/Thr pocket, and the other group consisting of eubacteria and the remaining archaea possesses the MI-type Ser/Thr pocket. This classification provides a useful framework for OST studies.

PubMed: 22559858
DOI: 10.1021/bi300076u

実験手法

X-RAY DIFFRACTION (1.75 Å)