PDBsum entry 1eii

Transport protein

PDB id: 1eii

Contents

Protein chain

134 a.a. *

Ligands

RTL

* Residue conservation analysis

PDB id:

1eii

Name:

Transport protein

Title:

Nmr structure of holo cellular retinol-binding protein ii

Structure:

Cellular retinol-binding protein ii. Chain: a. Synonym: crbp-ii. Engineered: yes

Source:

Rattus norvegicus. Norway rat. Organism_taxid: 10116. Cell: small intestinal enterocyte. Cellular_location: cytoplasm. Expressed in: escherichia coli. Expression_system_taxid: 562.

NMR struc:

25 models

Authors:

J.Lu,C.L.Lin,C.Tang,J.W.Ponder,J.L.Kao,D.P.Cistola,E.Li

Key ref:

J.Lu et al. (2000). Binding of retinol induces changes in rat cellular retinol-binding protein II conformation and backbone dynamics. J Mol Biol, 300, 619-632. PubMed id: 10884357 DOI: 10.1006/jmbi.2000.3883

Date:

25-Feb-00 Release date: 09-Aug-00

Protein chain

P06768  (RET2_RAT) -  Retinol-binding protein 2 from Rattus norvegicus

Seq: 134 a.a.

Struc: 134 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1006/jmbi.2000.3883

J Mol Biol 300:619-632 (2000)

PubMed id: 10884357

Binding of retinol induces changes in rat cellular retinol-binding protein II conformation and backbone dynamics.

J.Lu, C.L.Lin, C.Tang, J.W.Ponder, J.L.Kao, D.P.Cistola, E.Li.

ABSTRACT

The structure and backbone dynamics of rat holo cellular retinol-binding protein II (holo-CRBP II) in solution has been determined by multidimensional NMR. The final structure ensemble was based on 3980 distance and 30 dihedral angle restraints, and was calculated using metric matrix distance geometry with pairwise Gaussian metrization followed by simulated annealing. The average RMS deviation of the backbone atoms for the final 25 structures relative to their mean coordinates is 0.85(+/-0.09) A. Comparison of the solution structure of holo-CRBP II with apo-CRBP II indicates that the protein undergoes conformational changes not previously observed in crystalline CRBP II, affecting residues 28-35 of the helix-turn-helix, residues 37-38 of the subsequent linker, as well as the beta-hairpin C-D, E-F and G-H loops. The bound retinol is completely buried inside the binding cavity and oriented as in the crystal structure. The order parameters derived from the (15)N T(1), T(2) and steady-state NOE parameters show that the backbone dynamics of holo-CRBP II is restricted throughout the polypeptide. The T(2) derived apparent backbone exchange rate and amide (1)H exchange rate both indicate that the microsecond to second timescale conformational exchange occurring in the portal region of the apo form has been suppressed in the holo form.

Selected figure(s)

Figure 3.
Figure 3. (a) A stereodiagram of the final 25 NMR structures of holo-CRBP II in C a trace (in cyan) that are superim- posed on the four molecules of the X-ray structure of holo-CRBP II (in yellow). The bound retinol is highlighted in green and red in the NMR and X-ray structures, respectively. (b) A ribbon diagram of the mean NMR structure of CRBP II-retinol (ball/stick model) complex. These molecular images and the subsequent ones were generated using MOLMOL v.2.6 (Koradi et al., 1996).

Figure 5.
Figure 5. A stereodiagram of the bound retinols in the NMR ensemble (in green) superimposed on those in the crystal structures (in red). Residues that have NOE contacts with the ligand are shown in cyan along with the respective residues in the crystal structure (in yellow). Residues 20, 21, 24 (underneath the b-ionone ring of the bound retinol), 41, 59, 60 (above the b-ionone ring) and 63 (above the polyene chain) are omitted to allow a clear view of the ligand and the binding cavity.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2000, 300, 619-632) copyright 2000.

Figures were selected by an automated process.