Autor(es): Rossetto, Veronica
Data: 2020
Identificador Persistente: http://hdl.handle.net/10400.1/16690
Origem: Sapientia - Universidade do Algarve
Assunto(s): Interspecies interactions; Small molecule mimics; Quorum sensing signalling molecules; Bacterial communication.
Bacterial biofilms provide an advantageous spatial structure for colonization and cell maintenance as a community. This multicellular behaviour is regulated by a bacterial quorum-dependent mechanism, called the quorum sensing (QS) system that regulates other diverse social behaviours such as toxin production and virulence factors. This mechanism is regulated by signal molecules that regulate intra-specific, inter-specific and inter-kingdom interactions. For these reasons, this mechanism is strongly studied, as well as signalling molecules and analogues, such as alkyl-quinolone based compounds, for the disarming of pathogenic bacteria resistant to multi-drugs that plague public health worldwide. The path to a complete understanding of how this occurs, what are the conditions for such biological responses and what machinery and mechanisms exist for the perception and modulation of these interactions is still far from reaching a conclusion. Therefore, the present work seeks to evaluate compounds against behaviours dependent on the quorum sensing mechanism, as well as the effect of these compounds on the growth of harmful pathogens, such as Pseudomonas aeruginosa and Staphylococcus aureus. Providing information to assist in understanding these microbial interactions, as well as the development of new anti-infectious strategies and the fight against antimicrobial resistance. The tested compounds confirmed activities such as anti-biofilm, anti-swarming and anti-pyocyanin production. Of the twenty-three analogous compounds to the alkyl-quinolones screened thirteen presented some type of interference between the three evaluated phenotypes, five with significant antagonistic activities against P. aeruginosa PA14 and three against staphylococcal strains, such as S. aureus, Staphylococcus haemolyticus and Staphylococcus hominis. Thus, it is concluded that small molecules based on alkyl-quinolones are effective bioactive against QS dependent behaviours and can assist in unravelling microbial communication and its impacts on human society.
