Inhibition of LuxS by S-ribosylhomocysteine analogues containing a [4-aza]ribose ring
作者:Venkata L.A. Malladi、Adam J. Sobczak、Tiffany M. Meyer、Dehua Pei、Stanislaw F. Wnuk
DOI:10.1016/j.bmc.2011.07.043
日期:2011.9
LuxS (S-ribosylhomocysteinase) catalyzes the cleavage of the thioether linkage of S-ribosylhomocysteine (SRH) to produce homocysteine and 4,5-dihydroxy-2,3-pentanedione (DPD), the precursor to a small signaling molecule that mediates interspecies bacterial communication called autoinducer 2 (AI-2). Inhibitors of LuxS should interfere with bacterial interspecies communication and potentially provide a novel class of antibacterial agents. In this work, SRH analogues containing substitution of a nitrogen atom for the endocyclic oxygen as well as various deoxyriboses were synthesized and evaluated for LuxS inhibition. Two of the [4-aza] SRH analogues showed modest competitive inhibition (K-I similar to 40 mu M), while most of the others were inactive. One compound that contains a hemiaminal moiety exhibited time-dependent inhibition, consistent with enzyme-catalyzed ring opening and conversion into a more potent species (K-I* = 3.5 mu M). The structure-activity relationship of the designed inhibitors highlights the importance of both the homocysteine and ribose moieties for high-affinity binding to LuxS active site. (C) 2011 Elsevier Ltd. All rights reserved.