1TEE: Crystal Structure Of C205f Mutant Of Pks18 From Mycobacterium Tuberculosis

The superfamily of plant and bacterial type III polyketide synthases (PKSs) produces diverse metabolites with distinct biological functions. PKS18, a type III PKS from Mycobacterium tuberculosis, displays an unusual broad specificity for aliphatic long-chain acyl-coenzyme A (acyl-CoA) starter units (C(6)-C(20)) to produce tri- and tetraketide pyrones. The crystal structure of PKS18 reveals a 20 A substrate binding tunnel, hitherto unidentified in this superfamily of enzymes. This remarkable tunnel extends from the active site to the surface of the protein and is primarily generated by subtle changes of backbone dihedral angles in the core of the protein. Mutagenic studies combined with structure determination provide molecular insights into the structural elements that contribute to the chain length specificity of the enzyme. This first bacterial type III PKS structure underlines a fascinating example of the way in which subtle changes in protein architecture can generate metabolite diversity in nature.
PDB ID: 1TEEDownload
MMDB ID: 28686
PDB Deposition Date: 2004/5/25
Updated in MMDB: 2004/11
Experimental Method:
x-ray diffraction
Resolution: 2.9  Å
Source Organism:
Similar Structures:
Biological Unit for 1TEE: dimeric; determined by author and by software (PISA)
Molecular Components in 1TEE
Label Count Molecule
Proteins (2 molecules)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB