New bicyclic brominated furanones as potent autoinducer-2 quorum-sensing inhibitors against bacterial biofilm formation

Eur J Med Chem. 2017 Sep 8:137:76-87. doi: 10.1016/j.ejmech.2017.05.037. Epub 2017 May 17.

Abstract

Bacterial behaviors such as virulence factor secretion and biofilm formation are critical for survival, and are effectively regulated through quorum sensing, a mechanism of intra- and interspecies communication in response to changes in cell density and species complexity. Many bacterial species colonize host tissues and form a defensive structure called a biofilm, which can be the basis of inflammatory diseases. Periodontitis, a chronic inflammatory disease affecting the periodontium, is caused by subgingival biofilms related to periodontopathogens. In particular, Fusobacterium nucleatum is a major co-aggregation bridge organism in the formation and growth of subgingival biofilms, linking the early and late colonizers in periodontal biofilms. According to our previous study, the intergeneric quorum-sensing signal molecule autoinducer-2 (AI-2) of F. nucleatum plays a key role in intra- and interspecies interactions of periodontopathogens, and may be a good target for periodontal biofilm inhibition. Recently, brominated furanones produced by the macroalga Delisea pulchra were shown to inhibit biofilm formation via AI-2, and have been investigated toward the goal of increasing the inhibition effect. In this study, we describe the synthesis of new bromofuranone analogs, i.e., 3-(dibromomethylene)isobenzofuran-1(3H)-one derivatives, and demonstrate their inhibitory activities against biofilm formation by periodontopathogens, including F. nucleatum, Porphyromonas gingivalis, and Tannerella forsythia.

Keywords: AI-2 inhibitors; Bacterial biofilm; Brominated furanones; Quorum sensing.

MeSH terms

  • Anti-Bacterial Agents / chemical synthesis
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Biofilms / drug effects*
  • Dose-Response Relationship, Drug
  • Furans / chemical synthesis
  • Furans / pharmacology*
  • Fusobacterium nucleatum / drug effects
  • Homoserine / analogs & derivatives*
  • Homoserine / antagonists & inhibitors
  • Lactones / antagonists & inhibitors*
  • Microbial Sensitivity Tests
  • Molecular Structure
  • Porphyromonas gingivalis / drug effects
  • Quorum Sensing / drug effects
  • Structure-Activity Relationship
  • Tannerella forsythia / drug effects

Substances

  • Anti-Bacterial Agents
  • Furans
  • Lactones
  • N-octanoylhomoserine lactone
  • Homoserine