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 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: 41.55 kDa 
• Atom Count: 3083 
• Modelled Residue Count: 356 
• Deposited Residue Count: 364 
• Unique protein chains: 1

1I9A

STRUCTURAL STUDIES OF CHOLESTEROL BIOSYNTHESIS: MEVALONATE 5-DIPHOSPHATE DECARBOXYLASE AND ISOPENTENYL DIPHOSPHATE ISOMERASE

• DOI: 10.2210/pdb1I9A/pdb

• Classification: ISOMERASE
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2001-03-18 Released: 2001-03-28 
• Deposition Author(s): Bonanno, J.B., Edo, C., Eswar, N., Pieper, U., Romanowski, M.J., Ilyin, V., Gerchman, S.E., Kycia, H., Studier, F.W., Sali, A., Burley, S.K., New York SGX Research Center for Structural Genomics (NYSGXRC)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.279 
• R-Value Work: 0.229 
• R-Value Observed: 0.229 

Literature

Structural genomics of enzymes involved in sterol/isoprenoid biosynthesis.

Bonanno, J.B., Edo, C., Eswar, N., Pieper, U., Romanowski, M.J., Ilyin, V., Gerchman, S.E., Kycia, H., Studier, F.W., Sali, A., Burley, S.K.

(2001) Proc Natl Acad Sci U S A 98: 12896-12901

• PubMed: 11698677 
• DOI: 10.1073/pnas.181466998
• Primary Citation of Related Structures:  
  1I9A, 1FI4


• PubMed Abstract: 
  

X-ray structures of two enzymes in the sterol/isoprenoid biosynthesis pathway have been determined in a structural genomics pilot study. Mevalonate-5-diphosphate decarboxylase (MDD) is a single-domain alpha/beta protein that catalyzes the last of three sequential ATP-dependent reactions which convert mevalonate to isopentenyl diphosphate. Isopentenyl disphosphate isomerase (IDI) is an alpha/beta metalloenzyme that catalyzes interconversion of isopentenyl diphosphate and dimethylallyl diphosphate, which condense in the next step toward synthesis of sterols and a host of natural products. Homology modeling of related proteins and comparisons of the MDD and IDI structures with two other experimentally determined structures have shown that MDD is a member of the GHMP superfamily of small-molecule kinases and IDI is similar to the nudix hydrolases, which act on nucleotide diphosphatecontaining substrates. Structural models were produced for 379 proteins, encompassing a substantial fraction of both protein superfamilies. All three enzymes responsible for synthesis of isopentenyl diphosphate from mevalonate (mevalonate kinase, phosphomevalonate kinase, and MDD) share the same fold, catalyze phosphorylation of chemically similar substrates (MDD decarboxylation involves phosphorylation of mevalonate diphosphate), and seem to have evolved from a common ancestor. These structures and the structural models derived from them provide a framework for interpreting biochemical function and evolutionary relationships.

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Organizational Affiliation: 

Laboratories of Molecular Biophysics, Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ISOPENTENYL-DIPHOSPHATE DELTA-ISOMERASE	A, B	182	Escherichia coli	Mutation(s): 3  EC: 5.3.3.2
UniProt
Find proteins for Q46822 (Escherichia coli (strain K12)) Explore Q46822  Go to UniProtKB:  Q46822

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MN	C [auth A], D [auth B]	MANGANESE (II) ION Mn WAEMQWOKJMHJLA-UHFFFAOYSA-N

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A, B	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 0.279 
• R-Value Work: 0.229 
• R-Value Observed: 0.229 
• Space Group: P 4₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 72.758	α = 90
b = 72.758	β = 90
c = 204.471	γ = 90

Software Package:

Software Name	Purpose
MLPHARE	phasing
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-03-18 
• Released Date: 2001-03-28 
Deposition Author(s): Bonanno, J.B., Edo, C., Eswar, N., Pieper, U., Romanowski, M.J., Ilyin, V., Gerchman, S.E., Kycia, H., Studier, F.W., Sali, A., Burley, S.K., New York SGX Research Center for Structural Genomics (NYSGXRC)

Revision History  

• Version 1.0: 2001-03-28
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2021-02-03
  Changes: Database references, Derived calculations, Structure summary