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. 1999 Nov;8(11):2529–2532. doi: 10.1110/ps.8.11.2529

Molecular basis for triclosan activity involves a flipping loop in the active site.

X Qiu 1, C A Janson 1, R I Court 1, M G Smyth 1, D J Payne 1, S S Abdel-Meguid 1
PMCID: PMC2144207  PMID: 10595560

Abstract

The crystal structure of the Escherichia coli enoyl reductase-NAD+-triclosan complex has been determined at 2.5 A resolution. The Ile192-Ser198 loop is either disordered or in an open conformation in the previously reported structures of the enzyme. This loop adopts a closed conformation in our structure, forming van der Waals interactions with the inhibitor and hydrogen bonds with the bound NAD+ cofactor. The opening and closing of this flipping loop is likely an important factor in substrate or ligand recognition. The closed conformation of the loop appears to be a critical feature for the enhanced binding potency of triclosan, and a key component in future structure-based inhibitor design.

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Selected References

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