N-acyl homoserine lactonase (AiiA) (AiiA)

AiiA is a prominent N-acyl homoserine lactonase, first identified in Bacillus species, that serves as a key tool in quorum quenching strategies. It belongs to the metallo-beta-lactamase superfamily and requires two zinc ions for its catalytic activity, which involves the hydrolytic cleavage of the lactone ring in N-acyl homoserine lactones (AHLs) [Dong et al., 2000; Liu et al., 2005]. AHLs are essential signaling molecules used by many Gram-negative bacteria to coordinate group behaviors, including the expression of virulence factors and the formation of resilient biofilms [Grandclément et al., 2016]. By enzymatically degrading these signals, AiiA disrupts bacterial communication (quorum sensing), effectively attenuating the pathogenicity of organisms like Pseudomonas aeruginosa and Erwinia carotovora without exerting the strong selective pressure for resistance typical of traditional antibiotics [Dong et al., 2000]. This makes AiiA a significant candidate for therapeutic development in treating chronic infections and preventing biofouling in medical and industrial settings. While currently utilized primarily in agricultural and biotechnological research, its potential as a pathoblocker or anti-virulence agent represents a novel paradigm in managing multidrug-resistant bacterial diseases [Grandclément et al., 2016].

Other names

AHL lactonaseAHLaseN-acyl-L-homoserine lactone hydrolaseAutoinducer inactivation enzymeQuorum-quenching lactonase

Hydrolytic cleavage of the lactone ring in N-acyl homoserine lactones (AHLs), preventing them from binding to LuxR-type transcriptional regulators and thus inhibiting quorum-sensing-dependent gene expression [Dong et al., 2000; Liu et al., 2005].