3TJM

Crystal Structure of the Human Fatty Acid Synthase Thioesterase Domain with an Activate Site-Specific Polyunsaturated Fatty Acyl Adduct


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.48 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.190 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal structure of FAS thioesterase domain with polyunsaturated fatty acyl adduct and inhibition by dihomo-gamma-linolenic acid.

Zhang, W.Chakravarty, B.Zheng, F.Gu, Z.Wu, H.Mao, J.Wakil, S.J.Quiocho, F.A.

(2011) Proc.Natl.Acad.Sci.USA 108: 15757-15762

  • DOI: 10.1073/pnas.1112334108

  • PubMed Abstract: 
  • Human fatty acid synthase (hFAS) is a homodimeric multidomain enzyme that catalyzes a series of reactions leading to the de novo biosynthesis of long-chain fatty acids, mainly palmitate. The carboxy-terminal thioesterase (TE) domain determines the le ...

    Human fatty acid synthase (hFAS) is a homodimeric multidomain enzyme that catalyzes a series of reactions leading to the de novo biosynthesis of long-chain fatty acids, mainly palmitate. The carboxy-terminal thioesterase (TE) domain determines the length of the fatty acyl chain and its ultimate release by hydrolysis. Because of the upregulation of hFAS in a variety of cancers, it is a target for antiproliferative agent development. Dietary long-chain polyunsaturated fatty acids (PUFAs) have been known to confer beneficial effects on many diseases and health conditions, including cancers, inflammations, diabetes, and heart diseases, but the precise molecular mechanisms involved have not been elucidated. We report the 1.48 Å crystal structure of the hFAS TE domain covalently modified and inactivated by methyl γ-linolenylfluorophosphonate. Whereas the structure confirmed the phosphorylation by the phosphonate head group of the active site serine, it also unexpectedly revealed the binding of the 18-carbon polyunsaturated γ-linolenyl tail in a long groove-tunnel site, which itself is formed mainly by the emergence of an α helix (the "helix flap"). We then found inhibition of the TE domain activity by the PUFA dihomo-γ-linolenic acid; γ- and α-linolenic acids, two popular dietary PUFAs, were less effective. Dihomo-γ-linolenic acid also inhibited fatty acid biosynthesis in 3T3-L1 preadipocytes and selective human breast cancer cell lines, including SKBR3 and MDAMB231. In addition to revealing a novel mechanism for the molecular recognition of a polyunsaturated fatty acyl chain, our results offer a new framework for developing potent FAS inhibitors as therapeutics against cancers and other diseases.


    Organizational Affiliation

    Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Fatty acid synthase
A
283Homo sapiensMutation(s): 0 
Gene Names: FASN (FAS)
EC: 2.3.1.85
Find proteins for P49327 (Homo sapiens)
Go to Gene View: FASN
Go to UniProtKB:  P49327
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
7FA
Query on 7FA

Download SDF File 
Download CCD File 
A
methyl (R)-(6Z,9Z,12Z)-octadeca-6,9,12-trien-1-ylphosphonofluoridate
C19 H34 F O2 P
PYIHGLSRUVHCML-YMLCEXCJSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
7FAKi: 6360 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.48 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.190 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 50.915α = 90.00
b = 62.097β = 90.00
c = 76.511γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data collection
REFMACrefinement
CNSrefinement
CNSphasing
HKL-2000data reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-09-28
    Type: Initial release
  • Version 1.1: 2011-11-16
    Type: Database references