Proposed arrangement of proteins forming a bacterial type II polyketide synthase

Chem Biol. 2008 Nov 24;15(11):1156-65. doi: 10.1016/j.chembiol.2008.09.010.

Abstract

Aklanonic acid is synthesized by a type II polyketide synthase (PKS) composed of eight protein subunits. The network of protein interactions within this complex was investigated using a yeast two-hybrid system, by coaffinity chromatography and by two different computer-aided protein docking simulations. Results suggest that the ketosynthase (KS) alpha and beta subunits interact with each other, and that the KSalpha subunit also probably interacts with a malonyl-CoA:ACP acyltransferase (DpsD), forming a putative minimal synthase. We speculate that DpsD may physically inhibit the priming reaction, allowing the choice of propionate rather than acetate as the starter unit. We also suggest a structural role for the cyclase (DpsY) in maintaining the overall structural integrity of the complex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anthraquinones / metabolism
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism*
  • Chromatography, Affinity
  • Computer Simulation
  • Models, Molecular
  • Polyketide Synthases / chemistry*
  • Polyketide Synthases / metabolism*
  • Protein Binding
  • Protein Conformation
  • Two-Hybrid System Techniques

Substances

  • Anthraquinones
  • Bacterial Proteins
  • Polyketide Synthases
  • aklanonic acid