New insights into the binding and catalytic mechanisms of Bacillus thuringiensis lactonase: insights into B. thuringiensis AiiA mechanism.

ABSTRACT: The lactonase enzyme (AiiA) produced by Bacillus thuringiensis serves to degrade autoinducer-1 (AI-1) signaling molecules in what is an evolved mechanism by which to compete with other bacteria. Bioassays have been previously performed to determine whether the AI-1 aliphatic tail lengths have any effect on AiiA's bioactivity, however, data to date are conflicting. Additionally, specific residue contributions to the catalytic activity of AiiA provide for some interesting questions. For example, it has been proposed that Y194 serves to provide an oxyanion hole to AI-1 which is curious given the fact the substrate spans two Zn(2+) ions. These ions might conceivably provide enough charge to promote both ligand stability and the carbonyl activation necessary to drive a nucleophilic attack. To i

SUBMITTER: Charendoff MN 

PROVIDER: S-EPMC3776789 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature