Acylhomoserine lactone production and degradation by the fish pathogen Tenacibaculum maritimum, a member of the Cytophaga–Flavobacterium–Bacteroides (CFB) group


  • Editor: Craig Shoemaker

  • Present address: Rubén Avendaño-Herrera, Departamento de ciencias biológicas, Facultad de ciencias biológicas, Universidad de Andrés Bello, Santiago, Chile.

Correspondence: Ana Otero, Departamento de Microbiología, Facultad de Biología-CIBUS, Universidad de Santiago de Compostela, 15782 Santiago, Spain. Tel.: +34 98 156 3100, ext. 16967; fax: +34 98 159 2210; e-mail:


Tenacibaculum maritimum (formerly Flexibacter maritimus) is a filamentous, biofilm-forming member of the Cytophaga–Flavobacterium–Bacteroides group (or Bacteroidetes), which causes the widely distributed marine fish disease tenacibaculosis. A search for N-acylhomoserine lactones (AHLs) quorum-sensing (QS) signals in the culture media of nine representative strains of this species using different biosensor strains revealed the presence of short-type AHL activity in all of them. N-butyryl-l-homoserine lactone (C4-HSL) was identified in T. maritimum NCIMB2154T by LC-MS. A degradation activity for long-acyl AHLs (C10-HSL) was subsequently demonstrated in T. maritimum NCIMB2154T. The acidification of the culture medium after degradation did not allow the recovery of C10-HSL, which indicates a possible acylase-type degradation activity. Even though the physiological processes under the control of AHL-mediated QS in T. maritimum need to be further characterized, this discovery extends the paradigm of AHL-mediated QS signalling beyond the Proteobacteria and reinforces its ecological significance.