scholarly journals β-Barrel scaffolds for the grafting of extracellular loops from G-protein-coupled receptors

2012 ◽  
Vol 393 (11) ◽  
pp. 1341-1355 ◽  
Author(s):  
Reto Walser ◽  
Jörg H. Kleinschmidt ◽  
Arne Skerra ◽  
Oliver Zerbe
Keyword(s):  
G Protein ◽  
Structural Information ◽  
Binding Mode ◽  
G Protein Coupled Receptors ◽  
Peptide Ligand ◽  
Receptor Ligands ◽  
Natural Systems ◽  
Comprehensive Information ◽  
Chimeric Construct ◽  
G Protein Coupled

Abstract Owing to the difficulties in production and purification of G-protein-coupled receptors (GPCRs), relatively little structural information is available about this class of receptors. Here we aim at developing small chimeric proteins, displaying the extracellular ligand-binding motifs of a human GPCR, the Y receptor. This allows the study of ligand-receptor interactions in simplified systems. We present comprehensive information on the use of transmembrane (OmpA) and soluble (Blc) β-barrel scaffolds. Whereas Blc appeared to be not fully compatible with our approach, owing to problems with refolding of the hybrid constructs, loop-grafted versions of OmpA delivered encouraging results. Previously, we described a chimeric construct based on OmpA displaying all three extracellular Y1 receptor loops in different topologies and showing moderate affinity to one of the natural ligands. Now, we present detailed data on the interaction of these constructs with several Y receptor ligands along with data on new constructs. Our findings suggest a common binding mode for all ligands, which is mediated through the C-terminal residues of the peptide ligand, supporting the functional validity of these hybrid receptors. The observed binding affinities, however, are well below those observed for the natural receptors, clearly indicating limitations in mimicking the natural systems.

scholarly journals Applications of molecular replacement to G protein-coupled receptors

2013 ◽  
Vol 69 (11) ◽  
pp. 2287-2292 ◽  
Author(s):  
Andrew C. Kruse ◽  
Aashish Manglik ◽  
Brian K. Kobilka ◽  
William I. Weis
Keyword(s):  
G Protein ◽  
Structural Biology ◽  
Structural Information ◽  
G Protein Coupled Receptors ◽  
Integral Membrane Proteins ◽  
Molecular Replacement ◽  
Gpcr Activation ◽  
Health And Disease ◽  
Almost All ◽  
G Protein Coupled

G protein-coupled receptors (GPCRs) are a large class of integral membrane proteins involved in regulating virtually every aspect of human physiology. Despite their profound importance in human health and disease, structural information regarding GPCRs has been extremely limited until recently. With the advent of a variety of new biochemical and crystallographic techniques, the structural biology of GPCRs has advanced rapidly, offering key molecular insights into GPCR activation and signal transduction. To date, almost all GPCR structures have been solved using molecular-replacement techniques. Here, the unique aspects of molecular replacement as applied to individual GPCRs and to signaling complexes of these important proteins are discussed.

scholarly journals Data-Driven Analysis of Fluorination of Ligands of Aminergic G Protein Coupled Receptors

Biomolecules ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1647
Author(s):  
Wojciech Pietruś ◽  
Rafał Kurczab ◽  
Dagmar Stumpfe ◽  
Andrzej J. Bojarski ◽  
Jürgen Bajorath
Keyword(s):  
G Protein ◽  
G Protein Coupled Receptors ◽  
Ortho Position ◽  
Receptor Ligands ◽  
Clear Trend ◽  
Highly Active ◽  
Biological Compounds ◽  
Common Strategy ◽  
Negative Effect ◽  
G Protein Coupled

Currently, G protein-coupled receptors are the targets with the highest number of drugs in many therapeutic areas. Fluorination has become a common strategy in designing highly active biological compounds, as evidenced by the steadily increasing number of newly approved fluorine-containing drugs. Herein, we identified in the ChEMBL database and analysed 1554 target-based FSAR sets (non-fluorinated compounds and their fluorinated analogues) comprising 966 unique non-fluorinated and 2457 unique fluorinated compounds active against 33 different aminergic GPCRs. Although a relatively small number of activity cliffs (defined as a pair of structurally similar compounds showing significant differences of activity −ΔpPot > 1.7) was found in FSAR sets, it is clear that appropriately introduced fluorine can increase ligand potency more than 50-fold. The analysis of matched molecular pairs (MMPs) networks indicated that the fluorination of the aromatic ring showed no clear trend towards a positive or negative effect on affinity; however, a favourable site for a positive potency effect of fluorination was the ortho position. Fluorination of aliphatic fragments more often led to a decrease in biological activity. The results may constitute the rules of thumb for fluorination of aminergic receptor ligands and provide insights into the role of fluorine substitutions in medicinal chemistry.

Employing Rhodobacter sphaeroides to functionally express and purify human G protein-coupled receptors

2008 ◽  
Vol 389 (1) ◽  
pp. 69-78 ◽  
Author(s):  
Ankita Roy ◽  
Arun Kumar Shukla ◽  
Winfried Haase ◽  
Hartmut Michel
Keyword(s):  
G Protein ◽  
Rhodobacter Sphaeroides ◽  
Structural Information ◽  
Membrane Surface ◽  
Expression System ◽  
Gene Promoter ◽  
Photosynthetic Bacterium ◽  
G Protein Coupled Receptors ◽  
Recombinant Receptors ◽  
G Protein Coupled

AbstractG protein-coupled receptors (GPCRs) represent the largest class of cell surface receptors and play crucial roles in many cellular and physiological processes. Functional production of recombinant GPCRs is one of the main bottlenecks to obtaining structural information. Here, we report the use of a novel bacterial expression system based on the photosynthetic bacteriumRhodobacter sphaeroidesfor the production of human recombinant GPCRs. The advantage of employingR. sphaeroidesas a host lies in the fact that it provides much more membrane surface per cell compared to other typical expression hosts. The system was tailored to overexpress recombinant receptors under the control of the moderately strong and highly regulated superoperonic photosynthetic promoterpufQ. We tested this system for the expression of some class A GPCRs, namely, the human adenosine A2a receptor (A2aR), the human angiotensin AT1a receptor (AT1aR) and the human bradykinin B2 receptor (B2R). Several different constructs were examined and functional production of the recombinant receptors was achieved. The best-expressed receptor, AT1aR, was solubilized and affinity-purified. To the best of our knowledge, this is the first report of successful use of a bacterial host –R. sphaeroides– to produce functional recombinant GPCRs under the control of a photosynthetic gene promoter.

Bicyclic imidazole-4-one derivatives: a new class of antagonists for the orphan G protein-coupled receptors GPR18 and GPR55

MedChemComm ◽  
2014 ◽  
Vol 5 (5) ◽  
pp. 632-649 ◽  
Author(s):  
V. Rempel ◽  
K. Atzler ◽  
A. Behrenswerth ◽  
T. Karcz ◽  
C. Schoeder ◽  
...  
Keyword(s):  
G Protein ◽  
G Protein Coupled Receptors ◽  
Receptor Ligands ◽  
New Class ◽  
G Protein Coupled

GPR18 and GPR55 are orphan G protein-coupled receptors (GPCRs) that interact with certain cannabinoid (CB) receptor ligands.

NMR studies of CCK-8/CCK1 complex support membrane-associated pathway for ligand-receptor interaction

2002 ◽  
Vol 80 (5) ◽  
pp. 383-387 ◽  
Author(s):  
Craig Giragossian ◽  
Maria Pellegrini ◽  
Dale F Mierke
Keyword(s):  
G Protein ◽  
Structural Features ◽  
G Protein Coupled Receptors ◽  
Peptide Ligands ◽  
Receptor Interaction ◽  
Peptide Ligand ◽  
Receptor Subtype ◽  
Nmr Studies ◽  
Receptor Complexes ◽  
G Protein Coupled

The interaction of peptide ligands with their associated G-protein-coupled receptors has been examined by a number of different experimental approaches over the years. We have been developing an approach utilizing high-resolution NMR to determine the structural features of the peptide ligand, well-designed fragments of the receptor, and the ligand–receptor complexes formed upon titration of the peptide hormone. The results from these investigations provide evidence for a membrane-associated pathway for the initial interaction of peptide ligands with the receptor. Here, our results from the investigation of the interaction of CCK-8 with the CCK1 receptor are described. Our spectroscopic results clearly show that both CCK-8 and the regions of CCK1 with which it interacts are closely associated with the zwitterionic interface of the lipids utilized in our solution spectroscopic studies.Key words: G-protein-coupled receptors, NMR structural characterization, cholecystokinin, CCK-8, cholecystokinin receptor, subtype 1, CCK1, peptide hormones.

Sign in / Sign up

Export Citation Format

Share Document