4GXD

Crystal structure of D48V mutant of human GLTP bound with 12:0 disulfatide

4GXD の概要

• エントリーDOI: 10.2210/pdb4gxd/pdb
• 関連するPDBエントリー: 4GIX 4GVT
• 分子名称: Glycolipid transfer protein, N-{(2S,3R,4E)-1-[(3,6-di-O-sulfo-beta-D-galactopyranosyl)oxy]-3-hydroxyoctadec-4-en-2-yl}dodecanamide (3 entities in total)
• 機能のキーワード: gltp-fold, lipid transport
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Cytoplasm: Q9NZD2
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 24665.88

構造登録者

Samygina, V.R.,Ochoa-Lizarralde, B.,Popov, A.N.,Malinina, L. (登録日: 2012-09-04, 公開日: 2013-04-10, 最終更新日: 2024-03-20)

主引用文献

Samygina, V.R.,Ochoa-Lizarralde, B.,Popov, A.N.,Cabo-Bilbao, A.,Goni-de-Cerio, F.,Molotkovsky, J.G.,Patel, D.J.,Brown, R.E.,Malinina, L.
Structural insights into lipid-dependent reversible dimerization of human GLTP.
Acta Crystallogr.,Sect.D, 69:603-616, 2013

PubMed Abstract: Human glycolipid transfer protein (hsGLTP) forms the prototypical GLTP fold and is characterized by a broad transfer selectivity for glycosphingolipids (GSLs). The GLTP mutation D48V near the `portal entrance' of the glycolipid binding site has recently been shown to enhance selectivity for sulfatides (SFs) containing a long acyl chain. Here, nine novel crystal structures of hsGLTP and the SF-selective mutant complexed with short-acyl-chain monoSF and diSF in different crystal forms are reported in order to elucidate the potential functional roles of lipid-mediated homodimerization. In all crystal forms, the hsGLTP-SF complexes displayed homodimeric structures supported by similarly organized intermolecular interactions. The dimerization interface always involved the lipid sphingosine chain, the protein C-terminus (C-end) and α-helices 6 and 2, but the D48V mutant displayed a `locked' dimer conformation compared with the hinge-like flexibility of wild-type dimers. Differences in contact angles, areas and residues at the dimer interfaces in the `flexible' and `locked' dimers revealed a potentially important role of the dimeric structure in the C-end conformation of hsGLTP and in the precise positioning of the key residue of the glycolipid recognition centre, His140. ΔY207 and ΔC-end deletion mutants, in which the C-end is shifted or truncated, showed an almost complete loss of transfer activity. The new structural insights suggest that ligand-dependent reversible dimerization plays a role in the function of human GLTP.

PubMed: 23519669
DOI: 10.1107/S0907444913000024

実験手法

X-RAY DIFFRACTION (2.1 Å)