Table 2.

Studies demonstrating the QS disruption by signals synthesis inhibition. Abbreviations: AI, autoinducer; enoyl-ACP, enoyl-acyl carrier protein; HSL, L-homoserine lactone; PHL, propionyl homoserine lactones.

Models	Strains	Anti-QS agents	Target	Effects	Ref
In-vitro, Rats	Streptococcus pneumoniae D-39	Sinefungin	Inhibition of AI-2 synthesis via downregulating luxS, pfs, and speE expression	Inhibited pneumococcal biofilm growth in vitro and middle ear colonization in vivo	[62]
In-vitro	Pseudomonas aeruginosa	Sinefungin, butyryl-SAM, and S-adenosylhomocysteine	Inhibiting acyl-HSL signals	Inhibited formation of a covalent acyl–enzyme	[61]
In-vitro	Escherichia coli	Methylthio-DADMe-immucillin-A	Downregulating 5′-methylthioadenosine, S-adenosyl-homocysteine nucleosidase hydrolyzes	Disrupted key bacterial pathways of methylation, polyamine synthesis, methionine salvage, and quorum sensing	[64]
Mouse	Plasmodium falciparum	Triclosan	Inhibiting enoyl-ACP reductase	Protected against blood stages of malaria, enhanced elastic strength	[66]