1CTM

CRYSTAL STRUCTURE OF CHLOROPLAST CYTOCHROME F REVEALS A NOVEL CYTOCHROME FOLD AND UNEXPECTED HEME LIGATION

• PDB DOI: https://doi.org/10.2210/pdb1CTM/pdb

• Classification: ELECTRON TRANSPORT(CYTOCHROME)
• Organism(s): Brassica rapa
• Mutation(s): No 


• Deposited: 1994-01-02 Released: 1994-05-31 
• Deposition Author(s): Martinez, S.E., Huang, D., Szczepaniak, A., Cramer, W.A., Smith, J.L.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.277 
• R-Value Work: 0.198 
• R-Value Observed: 0.198 

Literature

Crystal structure of chloroplast cytochrome f reveals a novel cytochrome fold and unexpected heme ligation.

Martinez, S.E., Huang, D., Szczepaniak, A., Cramer, W.A., Smith, J.L.

(1994) Structure 2: 95-105

• PubMed: 8081747 
• DOI: https://doi.org/10.1016/s0969-2126(00)00012-5
• Primary Citation of Related Structures:  
  1CTM


• PubMed Abstract: 
  

  Cytochrome f is the high potential electron acceptor of the chloroplast cytochrome b6f complex, and is the electron donor to plastocyanin. The 285-residue cytochrome f subunit is anchored in the thylakoid membrane of the chloroplast by a single membrane-spanning segment near the carboxyl terminus. A soluble redox-active 252-residue lumen-side polypeptide with native spectroscopic and redox properties, missing the membrane anchor and carboxyl terminus, was purified from turnip chloroplasts for structural studies.

---

Organizational Affiliation: 

Department of Biological Sciences, Purdue University, West Lafayette, IN 47907-1392.

Biological Assembly 1  

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 27.94 kDa 
• Atom Count: 2,081 
• Modelled Residue Count: 250 
• Deposited Residue Count: 250 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CYTOCHROME F	A	250	Brassica rapa	Mutation(s): 0
UniProt
Find proteins for P36438 (Brassica rapa subsp. rapa) Explore P36438  Go to UniProtKB:  P36438

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
HEC	B [auth A]	HEME C C34 H34 Fe N4 O4 HXQIYSLZKNYNMH-LJNAALQVSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.277 
• R-Value Work: 0.198 
• R-Value Observed: 0.198 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 79.2	α = 90
b = 81.9	β = 90
c = 46.3	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1994-05-31 
Deposition Author(s): Martinez, S.E., Huang, D., Szczepaniak, A., Cramer, W.A., Smith, J.L.

Revision History  

• Version 1.0: 1994-05-31
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 2.0: 2021-03-10
  Changes: Atomic model, Data collection, Derived calculations, Non-polymer description, Other, Structure summary