Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 52.81 kDa 
• Atom Count: 4078 
• Modelled Residue Count: 451 
• Deposited Residue Count: 463 
• Unique protein chains: 1

7BQO

The structure of HpiI in complex with its substrate analogue

• PDB DOI: 10.2210/pdb7BQO/pdb

• Classification: BIOSYNTHETIC PROTEIN
• Organism(s): Hymenoscyphus scutula
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2020-03-25 Released: 2020-10-14 
• Deposition Author(s): Cai, Y.J., Ohashi, M., Zhou, J.H., Tang, Y.
• Funding Organization(s): National Science Foundation (NSF, China), Ministry of Science and Technology (MoST, China)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.53 Å
• R-Value Free: 0.182 
• R-Value Work: 0.166 
• R-Value Observed: 0.167 

Literature

An enzymatic Alder-ene reaction.

Ohashi, M., Jamieson, C.S., Cai, Y., Tan, D., Kanayama, D., Tang, M.C., Anthony, S.M., Chari, J.V., Barber, J.S., Picazo, E., Kakule, T.B., Cao, S., Garg, N.K., Zhou, J., Houk, K.N., Tang, Y.

(2020) Nature 586: 64-69

• PubMed: 32999480 
• DOI: 10.1038/s41586-020-2743-5
• Primary Citation of Related Structures:  
  7BQJ, 7BQK, 7BQL, 7BQO, 7BQP


• PubMed Abstract: 
  

An ongoing challenge in chemical research is to design catalysts that select the outcomes of the reactions of complex molecules. Chemists rely on organocatalysts or transition metal catalysts to control stereoselectivity, regioselectivity and periselectivity (selectivity among possible pericyclic reactions). Nature achieves these types of selectivity with a variety of enzymes such as the recently discovered pericyclases-a family of enzymes that catalyse pericyclic reactions ¹ . Most characterized enzymatic pericyclic reactions have been cycloadditions, and it has been difficult to rationalize how the observed selectivities are achieved ^2-13 . Here we report the discovery of two homologous groups of pericyclases that catalyse distinct reactions: one group catalyses an Alder-ene reaction that was, to our knowledge, previously unknown in biology; the second catalyses a stereoselective hetero-Diels-Alder reaction. Guided by computational studies, we have rationalized the observed differences in reactivities and designed mutant enzymes that reverse periselectivities from Alder-ene to hetero-Diels-Alder and vice versa. A combination of in vitro biochemical characterizations, computational studies, enzyme co-crystal structures, and mutational studies illustrate how high regioselectivity and periselectivity are achieved in nearly identical active sites.

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Organizational Affiliation: 

Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA, USA. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
HpiI	A	463	Hymenoscyphus scutula	Mutation(s): 0
UniProt
Find proteins for A0A1F8A906 (Aspergillus bombycis) Explore A0A1F8A906  Go to UniProtKB:  A0A1F8A906

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
B3P	E [auth A]	2-[3-(2-HYDROXY-1,1-DIHYDROXYMETHYL-ETHYLAMINO)-PROPYLAMINO]-2-HYDROXYMETHYL-PROPANE-1,3-DIOL C11 H26 N2 O6 HHKZCCWKTZRCCL-UHFFFAOYSA-N
F56 (Subject of Investigation/LOI)	B [auth A]	3-[(E,2S,4S)-2,4-dimethyloct-6-enoyl]-4-oxidanyl-1H-pyridin-2-one C15 H21 N O3 XOAZFUVQLCZQIQ-NNOMMRTBSA-N
GOL	D [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
IMD	C [auth A]	IMIDAZOLE C3 H5 N2 RAXXELZNTBOGNW-UHFFFAOYSA-O

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.53 Å
• R-Value Free: 0.182 
• R-Value Work: 0.166 
• R-Value Observed: 0.167 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 97.113	α = 90
b = 145.917	β = 90
c = 90.061	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
Aimless	data scaling
PDB_EXTRACT	data extraction
XDS	data reduction
PHENIX	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2020-03-25 
• Released Date: 2020-10-14 
Deposition Author(s): Cai, Y.J., Ohashi, M., Zhou, J.H., Tang, Y.

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Funding Organization	Location	Grant Number
National Science Foundation (NSF, China)	China	91856202
Ministry of Science and Technology (MoST, China)	China	2018YFA0901900

Revision History  

• Version 1.0: 2020-10-14
  Type: Initial release