ACPs in this domain have a fully conserved tryptophan.
Family alignment:
There are 3393 PKS_PP_betabranch domains in 810 proteins in SMART's nrdb database.
Click on the following links for more information.
Evolution (species in which this domain is found)
Taxonomic distribution of proteins containing PKS_PP_betabranch domain.
This tree includes only several representative species. The complete taxonomic breakdown of all proteins with PKS_PP_betabranch domain is also avaliable.
Click on the protein counts, or double click on taxonomic names to display all proteins containing PKS_PP_betabranch domain in the selected taxonomic class.
Literature (relevant references for this domain)
Primary literature is listed below; Automatically-derived, secondary literature is also avaliable.
A conserved motif flags acyl carrier proteins for beta-branching in polyketidesynthesis.
Nat Chem Biol. 2013; 9: 685-92
Display abstract
Type I polyketide synthases often use programmed beta-branching, via enzymes of a'hydroxymethylglutaryl-CoA synthase (HCS) cassette', to incorporate various side chains at the second carbon from the terminal carboxylic acid of growingpolyketide backbones. We identified a strong sequence motif in acyl carrierproteins (ACPs) where beta-branching is known to occur. Substituting ACPsconfirmed a correlation of ACP type with beta-branching specificity. Althoughthese ACPs often occur in tandem, NMR analysis of tandem beta-branching ACPsindicated no ACP-ACP synergistic effects and revealed that the conserved sequencemotif forms an internal core rather than an exposed patch. Modeling andmutagenesis identified ACP helix III as a probable anchor point of the ACP-HCScomplex whose position is determined by the core. Mutating the core affects ACPfunctionality, whereas ACP-HCS interface substitutions modulate systemspecificity. Our method for predicting beta-carbon branching expands thepotential for engineering new polyketides and lays a basis for determiningspecificity rules.
