Transition state analogs of 5'-methylthioadenosine nucleosidase disrupt quorum sensing.
Gutierrez, J.A., Crowder, T., Rinaldo-Matthis, A., Ho, M.C., Almo, S.C., Schramm, V.L.(2009) Nat Chem Biol 5: 251-257
- PubMed: 19270684 
- DOI: https://doi.org/10.1038/nchembio.153
- Primary Citation of Related Structures:  
3DP9 - PubMed Abstract: 
5'-Methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN) is a bacterial enzyme involved in S-adenosylmethionine-related quorum sensing pathways that induce bacterial pathogenesis factors. Transition state analogs MT-DADMe-Immucillin-A, EtT-DADMe-Immucillin-A and BuT-DADMe-Immucillin-A are slow-onset, tight-binding inhibitors of Vibrio cholerae MTAN (VcMTAN), with equilibrium dissociation constants of 73, 70 and 208 pM, respectively. Structural analysis of VcMTAN with BuT-DADMe-Immucillin-A revealed interactions contributing to the high affinity. We found that in V. cholerae cells, these compounds are potent MTAN inhibitors with IC(50) values of 27, 31 and 6 nM for MT-, EtT- and BuT-DADMe-Immucillin-A, respectively; the compounds disrupt autoinducer production in a dose-dependent manner without affecting growth. MT- and BuT-DADMe-Immucillin-A also inhibited autoinducer-2 production in enterohemorrhagic Escherichia coli O157:H7 with IC(50) values of 600 and 125 nM, respectively. BuT-DADMe-Immucillin-A inhibition of autoinducer-2 production in both strains persisted for several generations and caused reduction in biofilm formation. These results support MTAN's role in quorum sensing and its potential as a target for bacterial anti-infective drug design.
Organizational Affiliation: 
Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York, USA.