Human Sterol Carrier Protein with unnatural amino acid 2,2'-bipyridine alanine incorporated at position 111

Experimental Data Snapshot

  • Resolution: 2.51 Å
  • R-Value Free: 0.300 
  • R-Value Work: 0.234 
  • R-Value Observed: 0.237 

wwPDB Validation   3D Report Full Report

This is version 2.2 of the entry. See complete history


Using BpyAla to generate copper artificial metalloenzymes: a catalytic and structural study.

Klemencic, E.Brewster, R.C.Ali, H.S.Richardson, J.M.Jarvis, A.G.

(2024) Catal Sci Technol 14: 1622-1632

  • DOI: https://doi.org/10.1039/d3cy01648j
  • Primary Citation of Related Structures:  
    8AF2, 8AF3

  • PubMed Abstract: 

    Artificial metalloenzymes (ArMs) have emerged as a promising avenue in the field of biocatalysis, offering new reactivity. However, their design remains challenging due to the limited understanding of their protein dynamics and how the introduced cofactors alter the protein scaffold structure. Here we present the structures and catalytic activity of novel copper ArMs capable of ( R )- or ( S )-stereoselective control, utilizing a steroid carrier protein (SCP) scaffold. To incorporate 2,2'-bipyridine (Bpy) into SCP, two distinct strategies were employed: either Bpy was introduced as an unnatural amino acid (2,2'-bipyridin-5-yl)alanine (BpyAla) using amber stop codon expression or via bioconjugation of bromomethyl-Bpy to cysteine residues. The resulting ArMs proved to be effective at catalysing an enantioselective Friedel-Crafts reaction with SCP_Q111BpyAla achieving the best selectivity with an enantioselectivity of 72% ee ( S ). Interestingly, despite using the same protein scaffold, different attachment strategies for Bpy at the same residue (Q111) led to a switch in the enantiopreference of the ArM. X-ray crystal structures of SCP_Q111CBpy and SCP_Q111BpyAla ArMs with bound Cu(ii) ions unveiled crucial differences in the orientation of the catalytic centre. Combining structural information, alanine scanning studies, and computational analysis shed light on the distinct active sites of the ArMs, clarifying that these active sites stabilise the nucleophilic substrate on different sides of the electrophile leading to the observed switch in enantioselectivity. This work underscores the importance of integrating structural studies with catalytic screening to unravel the intricacies of ArM behaviour and facilitate their development for targeted applications in biocatalysis.

  • Organizational Affiliation

    EaStCHEM School of Chemistry, University of Edinburgh Joseph Black Building David Brewster Road The King's Buildings Edinburgh EH9 3FJ UK amanda.jarvis@ed.ac.uk.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Enoyl-CoA hydratase 2
A, B
128Homo sapiensMutation(s): 0 
Gene Names: HSD17B4EDH17B4SDR8C1
EC: (PDB Primary Data), (PDB Primary Data)
UniProt & NIH Common Fund Data Resources
Find proteins for P51659 (Homo sapiens)
Explore P51659 
Go to UniProtKB:  P51659
PHAROS:  P51659
GTEx:  ENSG00000133835 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP51659
Sequence Annotations
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
Query on BP5
A, B
Experimental Data & Validation

Experimental Data

  • Resolution: 2.51 Å
  • R-Value Free: 0.300 
  • R-Value Work: 0.234 
  • R-Value Observed: 0.237 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 34.512α = 90
b = 50.523β = 90.732
c = 62.211γ = 90
Software Package:
Software NamePurpose
autoPROCdata reduction
xia2data scaling

Structure Validation

View Full Validation Report

Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
UK Research and Innovation (UKRI)United KingdomMR/S017402/1
Wellcome TrustUnited Kingdom204804/Z/16/Z

Revision History  (Full details and data files)

  • Version 1.0: 2023-08-16
    Type: Initial release
  • Version 2.0: 2023-11-15
    Changes: Atomic model, Data collection, Derived calculations
  • Version 2.1: 2024-02-28
    Changes: Database references
  • Version 2.2: 2024-04-03
    Changes: Database references