A structure-function analysis of interspecies antagonism by the 2-heptyl-4-alkyl-quinolone signal molecule from Pseudomonas aeruginosa.

A structure-function analysis of interspecies antagonism by the 2-heptyl-4-alkyl-quinolone signal molecule from Pseudomonas aeruginosa. Microbiology. 2019 Dec 20;: Authors: Ramos AF, Woods DF, Shanahan R, Cano R, McGlacken GP, Serra C, O'Gara F, Reen FJ Abstract In recent years, the alkyl-quinolone molecular framework has already provided a rich source of bioactivity for the development of novel anti-infective compounds. Based on the quorum-sensing signalling molecules 4-hydroxy-2-heptylquinoline (HHQ) and 3,4-dihydroxy-2-heptylquinoline (PQS) from the nosocomial pathogen Pseudomonas aeruginosa, modifications have been developed with markedly enhanced anti-biofilm bioactivity towards important fungal and bacterial pathogens, including Candida albicans and Aspergillus fumigatus. Here we show that antibacterial activity of HHQ against Vibrionaceae is species-specific and it requires an exquisite level of structural fidelity within the alkyl-quinolone molecular framework. Antibacterial activity was demonstrated against the serious human pathogens Vibrio vulnificus and Vibrio cholerae as well as a panel of bioluminescent squid symbiont Allivibrio fischeri isolates. In contrast, Vibrio parahaemolyticus growth and biofilm formation was unaffected in the presence of HHQ and all the structural variants tested. In general, modification to almost all of the molecule except the alkyl-chain end, led to loss of activity. This suggests that the ba...
Source: Microbiology - Category: Microbiology Authors: Tags: Microbiology Source Type: research