PDBsum entry 1obn

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Oxidoreductase PDB id
Jmol PyMol
Protein chain
329 a.a. *
Waters ×255
* Residue conservation analysis
PDB id:
Name: Oxidoreductase
Title: Isopenicillin n synthase aminoadipoyl-cysteinyl-aminobutyrate-fe-no complex
Structure: Isopenicillin n synthetase. Chain: a. Synonym: isopenicillin n synthase. Engineered: yes
Source: Emericella nidulans. Aspergillus nidulans. Organism_taxid: 162425. Strain: nm554. Expressed in: escherichia coli. Expression_system_taxid: 562.
1.30Å     R-factor:   0.167     R-free:   0.189
Authors: A.J.Long,I.J.Clifton,P.L.Roach,J.E.Baldwin,C.J.Schofield, P.J.Rutledge
Key ref: A.J.Long et al. (2003). Structural studies on the reaction of isopenicillin N synthase with the substrate analogue delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-alpha-aminobutyrate. Biochem J, 372, 687-693. PubMed id: 12622704
31-Jan-03     Release date:   02-Feb-04    
Go to PROCHECK summary

Protein chain
Pfam   ArchSchema ?
P05326  (IPNS_EMENI) -  Isopenicillin N synthase
331 a.a.
329 a.a.
Key:    PfamA domain  Secondary structure  CATH domain

 Enzyme reactions 
   Enzyme class: E.C.  - Isopenicillin-N synthase.
[IntEnz]   [ExPASy]   [KEGG]   [BRENDA]

Penicillin N and Deacetoxycephalosporin C Biosynthesis
      Reaction: N-((5S)-5-amino-5-carboxypentanoyl)-L-cysteinyl-D-valine + O2 = isopenicillin N + 2 H2O
+ O(2)
isopenicillin N
Bound ligand (Het Group name = ASV)
matches with 95.83% similarity
+ 2 × H(2)O
Molecule diagrams generated from .mol files obtained from the KEGG ftp site
 Gene Ontology (GO) functional annotation 
  GO annot!
  Cellular component     cellular_component   1 term 
  Biological process     oxidation-reduction process   3 terms 
  Biochemical function     oxidoreductase activity     4 terms  


    Added reference    
Biochem J 372:687-693 (2003)
PubMed id: 12622704  
Structural studies on the reaction of isopenicillin N synthase with the substrate analogue delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-alpha-aminobutyrate.
A.J.Long, I.J.Clifton, P.L.Roach, J.E.Baldwin, C.J.Schofield, P.J.Rutledge.
Isopenicillin N synthase (IPNS) is a non-haem iron(II) oxidase which catalyses the biosynthesis of isopenicillin N from the tripeptide delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-valine (ACV). Herein we report crystallographic studies to investigate the reaction of IPNS with the truncated substrate analogue delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-alpha-aminobutyrate (ACAb). It has been reported previously that this analogue gives rise to three beta-lactam products when incubated with IPNS: two methyl penams and a cepham. Crystal structures of the IPNS-Fe(II)-ACAb and IPNS-Fe(II)-ACAb-NO complexes have now been solved and are reported herein. These structures and modelling studies based on them shed light on the diminished product selectivity shown by IPNS in its reaction with ACAb and further rationalize the presence of certain key residues at the IPNS active site.

Literature references that cite this PDB file's key reference

  PubMed id Reference
20078029 C.D.Brown-Marshall, A.R.Diebold, and E.I.Solomon (2010).
Reaction coordinate of isopenicillin N synthase: oxidase versus oxygenase activity.
  Biochemistry, 49, 1176-1182.  
19598184 W.Ge, I.J.Clifton, A.R.Howard-Jones, J.E.Stok, R.M.Adlington, J.E.Baldwin, and P.J.Rutledge (2009).
Structural studies on the reaction of isopenicillin N synthase with a sterically demanding depsipeptide substrate analogue.
  Chembiochem, 10, 2025-2031.
PDB code: 2vcm
17907118 A.C.Stewart, I.J.Clifton, R.M.Adlington, J.E.Baldwin, and P.J.Rutledge (2007).
A cyclobutanone analogue mimics penicillin in binding to isopenicillin N synthase.
  Chembiochem, 8, 2003-2007.
PDB code: 2jb4
16444759 A.Daruzzaman, I.J.Clifton, R.M.Adlington, J.E.Baldwin, and P.J.Rutledge (2006).
Unexpected oxidation of a depsipeptide substrate analogue in crystalline isopenicillin N synthase.
  Chembiochem, 7, 351-358.
PDB codes: 1w3v 1w3x
The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB code is shown on the right.