Targeting multiple chorismate-utilizing enzymes with a single inhibitor: validation of a three-stage design.
Chorismate-utilizing enzymes are attractive antimicrobial drug targets due to their absence in humans and their central role in bacterial survival and virulence. The structural and mechanistic homology of a group of these inspired the goal of discovering inhibitors that target multiple enzymes. Previously, we discovered seven inhibitors of 4-amino-4-deoxychorismate synthase (ADCS) in an on-bead, fluorescent-based screen of a 2304-member one-bead-one-compound combinatorial library. The inhibitors comprise PAYLOAD and COMBI stages, which interact with active site and surface residues, respectively, and are linked by a SPACER stage. These seven compounds, and six derivatives thereof, also inhibit two other enzymes in this family, isochorismate synthase (IS) and anthranilate synthase (AS). The best binding compound inhibits ADCS, IS, and AS with K(i) values of 720, 56, and 80 microM, respectively. Inhibitors with varying SPACER lengths show the original choice of lysine to be optimal. Lastly, inhibition data confirm the PAYLOAD stage directs the inhibitors to the ADCS active site.
Ziebart
Kristin T
KT
Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, USA.
Dixon
Seth M
SM
Avila
Belem
B
El-Badri
Mohamed H
MH
Guggenheim
Kathryn G
KG
Kurth
Mark J
MJ
Toney
Michael D
MD
D000878:Anthranilate Synthase / Q000037:antagonists & inhibitors*; D000900:Anti-Bacterial Agents / Q000737:chemistry*; D019731:Carbon-Nitrogen Ligases / Q000037:antagonists & inhibitors*; D020134:Catalytic Domain; D002827:Chorismic Acid / Q000378:metabolism*; D016503:Drug Delivery Systems; D004791:Enzyme Inhibitors / Q000737:chemistry*; D006801:Humans; D019751:Intramolecular Transferases / Q000037:antagonists & inhibitors*; D000637:Transaminases
D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D000637:Transaminases; C066599:aminodeoxychorismate synthase; D000878:Anthranilate Synthase; D019751:Intramolecular Transferases; C058486:isochorismate synthase; D019731:Carbon-Nitrogen Ligases; D002827:Chorismic Acid