Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: gel filtration

Biological Assembly 2  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content

• Total Structure Weight: 90.59 kDa 
• Atom Count: 7192 
• Residue Count: 788 
• Unique protein chains: 1

6F8A

Crystal structure of cytochrome P450 CYP260A1 (S276I) bound with histidine

• DOI: 10.2210/pdb6F8A/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Sorangium cellulosum So ce56
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 2017-12-12 Released: 2018-03-14 
• Deposition Author(s): Jozwik, I.K., Thunnissen, A.M.W.H.
• Funding Organization(s): German Research Foundation, European Commission

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.35 Å
• R-Value Free: 0.194 
• R-Value Work: 0.178 
• R-Value Observed: 0.179 

Literature

Structure-Based Engineering of Steroidogenic CYP260A1 for Stereo- and Regioselective Hydroxylation of Progesterone.

Khatri, Y., Jozwik, I.K., Ringle, M., Ionescu, I.A., Litzenburger, M., Hutter, M.C., Thunnissen, A.W.H., Bernhardt, R.

(2018) ACS Chem Biol 13: 1021-1028

• PubMed: 29509407 
• DOI: 10.1021/acschembio.8b00026
• Structures With Same Primary Citation


• PubMed Abstract: 
  

The production of regio- and stereoselectively hydroxylated steroids is of high pharmaceutical interest and can be achieved by cytochrome P450-based biocatalysts. CYP260A1 from Sorangium cellulosum strain So ce56 catalyzes hydroxylation of C19 or C21 steroids at the very unique 1α-position. However, the conversion of progesterone (PROG) by CYP260A1 is very unselective. In order to improve its selectivity we applied a semirational protein engineering approach, resulting in two different, highly regio- and stereoselective mutants by replacing a single serine residue (S276) of the substrate recognition site 5 with an asparagine or isoleucine. The S276N mutant converted PROG predominantly into 1α-hydroxy-PROG, while the S276I mutant led to 17α-hydroxy-PROG. We solved the high-resolution crystal structures of the PROG-bound S276N and S276I mutants, which revealed two different binding modes of PROG in the active site. The orientations were consistent with the exclusive 1α- (pro-1α binding mode) and 17α-hydroxylation (pro-17α-binding mode) of S276N and S276I, respectively. We observed that water-mediated hydrogen bonds contribute to the stabilization of the polar C3 and C17 substituents of PROG. Both binding modes of PROG may be stabilized in the wild-type enzyme. The change in regioselectivity is mainly driven by destabilizing the alternative binding mode due to steric hindrance and hydrogen bond disruption, caused by the mutations of Ser276. Thus, for the first time, the change in the selectivity of cytochrome P450-mediated steroid hydroxylation created by rational mutagenesis can be explained by the obtained 3D structures of the substrate-bound mutants, providing the basis for further experiments to engineer the biocatalyst toward novel steroid hydroxylation positions.

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Organizational Affiliation: 

Department of Biochemistry , Campus B2.2 , 66123 , Saarland University , Saarbrücken , Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Cytochrome P450 CYP260A1	A, B	400	Sorangium cellulosum So ce56	Mutation(s): 1  Gene Names: sce1588 EC: 1.14
Find proteins for A9FDB7 (Sorangium cellulosum (strain So ce56)) Explore A9FDB7  Go to UniProtKB:  A9FDB7

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HEM	A, B	PROTOPORPHYRIN IX CONTAINING FE C34 H32 Fe N4 O4 KABFMIBPWCXCRK-RGGAHWMASA-L
HIS	A, B	HISTIDINE C6 H10 N3 O2 HNDVDQJCIGZPNO-YFKPBYRVSA-O

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.35 Å
• R-Value Free: 0.194 
• R-Value Work: 0.178 
• R-Value Observed: 0.179 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 101.221	α = 90
b = 65.151	β = 112.81
c = 128.533	γ = 90

Software Package:

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

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2017-12-12 
• Released Date: 2018-03-14 
Deposition Author(s): Jozwik, I.K., Thunnissen, A.M.W.H.

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Funding Organization	Location	Grant Number
German Research Foundation	Germany	BE 1343/23-1/23-2
European Commission	Netherlands	289217

Revision History 

• Version 1.0: 2018-03-14
  Type: Initial release
  
• Version 1.1: 2018-05-02
  Changes: Data collection, Database references