PDBsum entry: 2rh1

Membrane protein / hydrolase

PDB-id: 2rh1

Contents

Description

Header details

Header records

References

PROCHECK

Protein chain

442 a.a. *

Ligands

MAL

SO4 ×6

CAU

BU1 ×2

ACM

CLR ×3

PLM

12P

Waters ×48

* Residue conservation analysis

Tools

Clefts Calculation

PDB id:

2rh1

Name:

Membrane protein / hydrolase

Title:

High resolution crystal structure of human b2-adrenergic g protein-coupled receptor.

Structure:

Beta-2-adrenergic receptor/t4-lysozyme chimera. Chain: a. Synonym: beta-2 adrenergic receptor, beta-2 adrenoceptor, beta-2 adrenoreceptor / lysis protein, muramidase, endolysin. Engineered: yes. Mutation: yes

Source:

Homo sapiens, enterobacteria phage t4. Human,. Organism_taxid: 9606,10665. Strain: ,. Gene: adrb2, adrb2r, b2ar / e. Expressed in: spodoptera frugiperda. Expression_system_taxid: 7108. Other_details: the construct has been obtained by overlapping extension pcr

UniProt:

P07550 (ADRB2_HUMAN)

Seq:

Struc:

Seq:

Struc:

Seq:

413 a.a.

Struc:

442 a.a.*

Key:	PfamA domain
Secondary structure	CATH domain

* PDB and UniProt seqs differ at 149 residue positions (black crosses)

Resolution:

2.40Å

R-factor:

0.198

R-free:

0.232

Authors:

V.Cherezov,D.M.Rosenbaum,M.A.Hanson,S.G.F.Rasmussen, F.S.Thian,T.S.Kobilka,H.J.Choi,P.Kuhn,W.I.Weis,B.K.Kobilka, R.C.Stevens,Accelerated Technologies Center For Gene To 3d Structure (Atcg3d)

Key ref:

V.Cherezov et al. (2007). High-resolution crystal structure of an engineered human beta2-adrenergic G protein-coupled receptor.. Science, 318, 1258-1265. [PubMed id: 17962520] [DOI: 10.1126/science.1150577]

Date:

05-Oct-07

Release date:

30-Oct-07

Related entries:

Atcg3d_17 related db: targetdb

Quick_links

Procheck

Clefts

Surface

ProFunc

Key reference

DOI no: 10.1126/science.1150577

Science 318:1258-1265 (2007)

PubMed id: 17962520

High-resolution crystal structure of an engineered human beta2-adrenergic G protein-coupled receptor.

V.Cherezov, D.M.Rosenbaum, M.A.Hanson, S.G.Rasmussen, F.S.Thian, T.S.Kobilka, H.J.Choi, P.Kuhn, W.I.Weis, B.K.Kobilka, R.C.Stevens.

ABSTRACT

Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors constitute the largest family of eukaryotic signal transduction proteins that communicate across the membrane. We report the crystal structure of a human beta2-adrenergic receptor-T4 lysozyme fusion protein bound to the partial inverse agonist carazolol at 2.4 angstrom resolution. The structure provides a high-resolution view of a human G protein-coupled receptor bound to a diffusible ligand. Ligand-binding site accessibility is enabled by the second extracellular loop, which is held out of the binding cavity by a pair of closely spaced disulfide bridges and a short helical segment within the loop. Cholesterol, a necessary component for crystallization, mediates an intriguing parallel association of receptor molecules in the crystal lattice. Although the location of carazolol in the beta2-adrenergic receptor is very similar to that of retinal in rhodopsin, structural differences in the ligand-binding site and other regions highlight the challenges in using rhodopsin as a template model for this large receptor family.

Selected figure(s)

Figure 3.
Fig. 3. Surface representation of β[2]AR colored by calculated charge from red (–10 k[b]T/e[c]) to blue (+10 k[b]T/e[c]) using a dielectric constant of 70. (A) Three main areas of interest are indicated. The binding-site cleft is negatively charged, as is a groove between helices III, IV, and V. The third region is an overall positive charge in the region of the ionic lock and Asp-Arg-Tyr motif on the cytoplasmic face. The overall result is a highly polarized molecule that may use its negative charge to facilitate binding of catecholamine ligands. The presence of a negative charge in the groove between helices III, IV, and V is unexpected, as it is in the middle of the lipid membrane. This charge may be partially derived from the presence of an unpaired glutamate at position 122^3.41. The effective charge in this region is likely greater than shown here because of its location in the low-dielectric environment of the lipid membrane. (B) View rotated 90° from (A), showing the negatively charged binding-site cleft (top) and the positively charged cytoplasmic face (bottom). Poisson-Boltzmann electrostatics were calculated using APBS (52) as implemented in PyMOL (75). PyMOL was used exclusively in the preparation of all figures.

Figure 5.
Fig. 5. Ligand-binding characterization and comparison to rhodopsin. (A) View looking down on the plane of the membrane from the extracellular surface, showing a detailed representation of the carazolol-binding site in β[2]AR-T4L. Carazolol is shown as sticks with carbon atoms colored yellow. β[2]AR-T4L residues contributing to carazolol binding are shown in green and labeled. Electron density is contoured at 5 from an F[obs] – F[calc] omit map calculated without the contribution of carazolol. Abbreviations: D, Asp; F, Phe; N, Asn; S, Ser; W, Trp; Y, Tyr. (B) Binding orientation comparison between 11-cis-retinal in rhodopsin and carazolol in β[2]AR-T4L. Van der Waals surfaces for carazolol and retinal are represented as dots to accentuate the close-packing interactions. Retinal in the 11-cis conformation (pink) binds deep in the active site of rhodopsin as compared to carazolol (blue), packing its β-ionone ring between Tyr268^6.51 and Phe212^5.47 (cyan) and blocking movement of Trp265^6.48 (magenta) into the space. The β-ionone ring of all-trans-retinal in activated rhodopsin would not block Trp265^6.48 from rotating into the space, allowing a rotameric shift into its proposed active form. (C) Four residues are involved in the toggle switch mechanism of β[2]AR-T4L. Phe290^6.52 (magenta) is sandwiched between Phe208^5.47 (tan) and Phe289^6.51 (tan), forming a ring-face aromatic interaction. Like rhodopsin, an activation step is thought to occur by a rotameric change of Trp286^6.48 (magenta), which would displace Phe290^6.52. Carazolol is shown to interact extensively with the sandwich motif; however, few interactions are seen with Trp286^6.48. The 6.52 position in β[2]AR-T4L is occupied by Phe290^6.52, as opposed to Ala269^6.52 in rhodopsin, where the β-ionone ring replaces an aromatic protein side chain in forming the sandwich interactions. The aromatic character of the sandwich is otherwise maintained by Phe289^6.51 and Phe208^5.47 in β[2]AR-T4L.

The above figures are reprinted by permission from the AAAs: Science (2007, 318, 1258-1265) copyright 2007.

Figures were selected by an automated process.