The invention is directed to novel probiotic bacterial strains that colonize animal tissues, and in particular the gastrointestinal (GI) tract of aquatic animals grown in aquaculture environments and may further be engineered to express and deliver interfering RNA molecules configured to downregulate expression of one or more pathogen, or endogenous host genes.

A composition including nano- or microspheres, and/or tubular nanostructures, each made of a plurality of aromatic dipeptides including end-capping modified aromatic dipeptides, non-modified aromatic dipeptides, or a combination thereof; and encapsulating an esterase or a functional fragment thereof; as well as methods of use. The plurality of aromatic dipeptides may include the end-capping modified aromatic dipeptides only.

Provided herein are lactonases. In one embodiment, the lactonases are metallo-β-lactamase-like lactonase (MLL) enzymes having altered characteristics such as altered catalytic activity and/or altered substrate specificity. Also provided are genetically modified microbes able to express a MLL enzyme, compositions that include a MLL enzyme, and methods of using a MLL enzyme.

Mutated phosphotriesterase-like lactonases or functional fragments can be used in methods for treating or preventing infection of a bacterium in a host, such as a plant or a part, organ or a plant propagation material. The methods include applying the mutated phosphotriesterase-like lactonases or the wild-type enzyme to the host Cells expressing the mutated phosphotriesterase-like lactonases can also be produced using nucleic acid molecules and vectors encoding the mutated phosphotriesterase-like lactonases or functional fragments.

One or more quorum silencing enzymes entrapped in an organopolysiloxane matrix, formulations comprising the enzymes, methods for obtaining the entrapped enzymes by co-gelation and methods of treating intestinal diseases.

A stabilized enzyme product comprising composite particles that comprise an enzyme component within a nanoporous organopolysiloxane matrix. The enzyme component is capable of hydrolyzing one or more acyl-homoserine lactones and constitutes about 0.01 wt % to about 40 wt % of the composite particles on a dry weight basis. The composite particles have a density in a range of about 0.02 g/cm.sup.3 to about 0.5 g/cm.sup.3, an accessible surface area in a range of about 250 m.sup.2/g to about 600 m.sup.2/g, and fractal three-dimensional structures.

The present invention is directed to an isolated polypeptide being a quorum-quenching N-acyl-homoserine lactonase, compositions including same, and methods of using same, such as for reducing or inhibiting formation of load of an organic-based contaminant.

One or more quorum silencing enzymes entrapped in an organopolysiloxane matrix, formulations comprising the enzymes, methods for obtaining the entrapped enzymes by co-gelation and methods of treating intestinal diseases.

The present invention relates to new mutated lactonases, to their uses as well as to compositions containing them.