4Z2Y

Crystal structure of methyltransferase CalO6

• PDB DOI:  https://doi.org/10.2210/pdb4Z2Y/pdb

• Classification: TRANSFERASE
• Organism(s): Micromonospora echinospora
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2015-03-30 Released: 2015-07-22 
• Deposition Author(s): Hou, C., Garneau-Tsodikova, S., Tsodikov, O.V.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.40 Å
• R-Value Free: 0.333 
• R-Value Work: 0.325 
• R-Value Observed: 0.325 

Literature

Crystal structure of O-methyltransferase CalO6 from the calicheamicin biosynthetic pathway: a case of challenging structure determination at low resolution.

Tsodikov, O.V., Hou, C., Walsh, C.T., Garneau-Tsodikova, S.

(2015) BMC Struct Biol 15: 13-13

• PubMed: 26170207 
• DOI: https://doi.org/10.1186/s12900-015-0040-6
• Primary Citation of Related Structures:  
  4Z2Y


• PubMed Abstract: 
  

Calicheamicins (CAL) are enedyine natural products with potent antibiotic and cytotoxic activity, used in anticancer therapy. The O-methyltransferase CalO6 is proposed to catalyze methylation of the hydroxyl moiety at the C2 position of the orsellinic acid group of CAL.

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Organizational Affiliation: 

Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, 40536-0596, Lexington, KY, USA. [e-mail].

Biological Assembly 1  

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

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

Macromolecule Content

• Total Structure Weight: 38.71 kDa 
• Atom Count: 2,194 
• Modelled Residue Count: 299 
• Deposited Residue Count: 359 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CalO6	A	359	Micromonospora echinospora	Mutation(s): 0  Gene Names: calO6

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HG	B [auth A], C [auth A]	MERCURY (II) ION Hg BQPIGGFYSBELGY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.40 Å
• R-Value Free: 0.333 
• R-Value Work: 0.325 
• R-Value Observed: 0.325 
• Space Group: H 3 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 126.828	α = 90
b = 126.828	β = 90
c = 105.659	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling
PHENIX	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2015-07-22 
Deposition Author(s): Hou, C., Garneau-Tsodikova, S., Tsodikov, O.V.

Revision History  

• Version 1.0: 2015-07-22
  Type: Initial release
  
• Version 1.1: 2015-07-29
  Changes: Database references