1B9I

CRYSTAL STRUCTURE OF 3-AMINO-5-HYDROXYBENZOIC ACID (AHBA) SYNTHASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.222 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Crystal structure of 3-amino-5-hydroxybenzoic acid (AHBA) synthase.

Eads, J.C.Beeby, M.Scapin, G.Yu, T.W.Floss, H.G.

(1999) Biochemistry 38: 9840-9849

  • DOI: 10.1021/bi990018q
  • Primary Citation of Related Structures:  1B9H

  • PubMed Abstract: 
  • The biosynthesis of ansamycin antibiotics, including rifamycin B, involves the synthesis of an aromatic precursor, 3-amino-5-hydroxybenzoic acid (AHBA), which serves as starter for the assembly of the antibiotics' polyketide backbone. The terminal en ...

    The biosynthesis of ansamycin antibiotics, including rifamycin B, involves the synthesis of an aromatic precursor, 3-amino-5-hydroxybenzoic acid (AHBA), which serves as starter for the assembly of the antibiotics' polyketide backbone. The terminal enzyme of AHBA formation, AHBA synthase, is a dimeric, pyridoxal 5'-phosphate (PLP) dependent enzyme with pronounced sequence homology to a number of PLP enzymes involved in the biosynthesis of antibiotic sugar moieties. The structure of AHBA synthase from Amycolatopsis mediterranei has been determined to 2.0 A resolution, with bound cofactor, PLP, and in a complex with PLP and an inhibitor (gabaculine). The overall fold of AHBA synthase is similar to that of the aspartate aminotransferase family of PLP-dependent enzymes, with a large domain containing a seven-stranded beta-sheet surrounded by alpha-helices and a smaller domain consisting of a four-stranded antiparallel beta-sheet and four alpha-helices. The uninhibited form of the enzyme shows the cofactor covalently linked to Lys188 in an internal aldimine linkage. On binding the inhibitor, gabaculine, the internal aldimine linkage is broken, and a covalent bond is observed between the cofactor and inhibitor. The active site is composed of residues from two subunits of AHBA synthase, indicating that AHBA synthase is active as a dimer.


    Organizational Affiliation

    School of Biochemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTEIN (3-AMINO-5-HYDROXYBENZOIC ACID SYNTHASE)
A
388Amycolatopsis mediterranei (strain S699)Gene Names: rifK (rifD)
EC: 4.2.1.144, 2.6.1.-
Find proteins for O52552 (Amycolatopsis mediterranei (strain S699))
Go to UniProtKB:  O52552
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PXG
Query on PXG

Download SDF File 
Download CCD File 
A
3-[O-PHOSPHONOPYRIDOXYL]--AMINO-BENZOIC ACID
C15 H17 N2 O7 P
WSOQXCGRIUHULI-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.222 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 89.630α = 90.00
b = 89.630β = 90.00
c = 126.570γ = 120.00
Software Package:
Software NamePurpose
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1999-08-13
    Type: Initial release
  • Version 1.1: 2008-04-26
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance