IN VITRO OF ANTI QUORUM SENSING BACTERIA DEGRADING ACYL HOMOSERINE LACTONE OF Aeromonas hydrophila

Hessy Novita*, Iman Rusmana, Munti Yuhana,  Fachriyan H. Pasaribu, and Angela M. Lusiastuti
 
Research Institute for Freshwater Aquaculture
Jl. Sempur No. 1 Bogor - West Java, INDONESIA
hesta_biotek@yahoo.com

 

Anti Quorum sensing (AQS) was process of inactivation or degradation of Quorum Sensing signal molecules (AHL) without affecting growth of the bacteria. The  AQS bacteria is one of strategies to inhibit QS are promising for the control of infectious diseases or antibiotic resistant bacterial pathogens. The aim of the reseacrh was to study  in vitro co-culture system between AQS bacteria with  Aeromonas hydrophila as pathogen caused Motile Aeromonad Septicaemia (MAS) in fresh water fish.

The in vitro co culture (AQS bacteria and Aeromonas hydrophila) count increased continuously in treated groups (in 24h) load only increased but Aeromonas hydrophila count decreased constantly during the experimental, can be seen in Table 1.

The AQS bacteria may produce that enzyme as a defence strategy against the pathogen. They were able to utilize AHL and enzymatic degradation product as sole carbon and nitrogen sources Therefore, the AQS bacteria can block the QS system of their bacterial competitor to obtain a selective advantage without affecting growth of the bacteria (Figure 1). Those reasons then were supported by the facts that AQS bacteria were also used increasingly as probiotics in aquaculture.