PDBsum entry 1eu8

Sugar binding protein

PDB id: 1eu8

Contents

Protein chain

407 a.a. *

Ligands

GLC-GLC

Metals

_CL ×5

_PT ×3

Waters ×287

* Residue conservation analysis

PDB id:

1eu8

Name:

Sugar binding protein

Title:

Structure of trehalose maltose binding protein from thermococcus litoralis

Structure:

Trehalose/maltose binding protein. Chain: a. Engineered: yes

Source:

Thermococcus litoralis. Organism_taxid: 2265. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

1.90Å R-factor: 0.198 R-free: 0.232

Authors:

J.Diez,K.Diederichs,G.Greller,R.Horlacher,W.Boos,W.Welte

Key ref:

J.Diez et al. (2001). The crystal structure of a liganded trehalose/maltose-binding protein from the hyperthermophilic Archaeon Thermococcus litoralis at 1.85 A. J Mol Biol, 305, 905-915. PubMed id: 11162101 DOI: 10.1006/jmbi.2000.4203

Date:

14-Apr-00 Release date: 14-Mar-01

Protein chain

Q7LYW7  (MALE_THELN) -  Trehalose/maltose-binding protein MalE from Thermococcus litoralis (strain ATCC 51850 / DSM 5473 / JCM 8560 / NS-C)

Seq: 450 a.a.

Struc: 407 a.a.*

* PDB and UniProt seqs differ at 4 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1006/jmbi.2000.4203

J Mol Biol 305:905-915 (2001)

PubMed id: 11162101

The crystal structure of a liganded trehalose/maltose-binding protein from the hyperthermophilic Archaeon Thermococcus litoralis at 1.85 A.

J.Diez, K.Diederichs, G.Greller, R.Horlacher, W.Boos, W.Welte.

ABSTRACT

We report the crystallization and structure determination at 1.85 A of the extracellular, membrane-anchored trehalose/maltose-binding protein (TMBP) in complex with its substrate trehalose. TMBP is the substrate recognition site of the high-affinity trehalose/maltose ABC transporter of the hyperthermophilic Archaeon Thermococcus litoralis. In vivo, this protein is anchored to the membrane, presumably via an N-terminal cysteine lipid modification. The crystallized protein was N-terminally truncated, resulting in a soluble protein exhibiting the same binding characteristics as the wild-type protein. The protein shows the characteristic features of a transport-related, substrate-binding protein and is structurally related to the maltose-binding protein (MBP) of Escherichia coli. It consists of two similar lobes, each formed by a parallel beta-sheet flanked by alpha-helices on both sides. Both are connected by a hinge region consisting of two antiparallel beta-strands and an alpha-helix. As in MBP, the substrate is bound in the cleft between the lobes by hydrogen bonds and hydrophobic interactions. However, compared to maltose binding in MBP, direct hydrogen bonding between the substrate and the protein prevails while apolar contacts are reduced. To elucidate factors contributing to thermostability, we compared TMBP with its mesophilic counterpart MBP and found differences known from similar investigations. Specifically, we find helices that are longer than their structurally equivalent counterparts, and fewer internal cavities.

Selected figure(s)

Figure 1.
Figure 1. Ribbon model of TMBP with bound trehalose (shown as a ball and stick model). The N-terminal and C-terminal lobes are coloured yellow and blue, respectively. The bound trehalose is shown as a bond model and coloured black; a-helices and b-strands are labelled according to Figure 2(b).

Figure 3.
Figure 3. Stereo representation of a |3F[o] -2F[c]| electron density map of TMBP at 2.4 s around the bound a,a-trehalose moiety. Carbon atoms are coloured grey, nitrogen atoms are coloured blue and oxygen atoms are coloured red. The map is coloured green.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2001, 305, 905-915) copyright 2001.

Figures were selected by an automated process.