Article

Pseudomonas aeruginosa porphobilinogen synthase assembly state regulators: hit discovery and initial SAR studies.

Fox Chase Chemical Diversity Center, Inc., Pennsylvania Center for Drug Discovery, Pennsylvania Biotechnology Center, Doylestown, PA 18902 USA.
ARKIVOC : free online journal of organic chemistry / Arkat-USA, Inc 06/2010; 2010:175-188.
Source: PubMed

ABSTRACT Porphobilinogen synthase (PBGS) catalyzes the first common step in the biosynthesis of the essential heme, chlorophyll and vitamin B(12) heme pigments. PBGS activity is regulated by assembly state, with certain oligomers exhibiting biological activity and others either partially or completely inactive, affording an innovative means of allosteric drug action. Pseudomonas aeruginosa PBGS is functionally active as an octamer, and inactive as a dimer. We have identified a series of compounds that stabilize the inactive P. aeruginosa dimer by a computational prescreen followed by native PAGE gel mobility shift analysis. From those results, we have prepared related thiadiazoles and evaluated their ability to regulate P. aeruginosa PBGS assembly state.

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