Proteolytic degradation of oral biofilms in vitro and in vivo: potential of proteases originating from Euphausia superba for plaque control

This paper deals with enzymatic removal of dental plaque, in vitro as well as in vivo, using proteases from the Antarctic krill shrimp (Euphausia supe rba), referred to as Krillase (R). Krillase exhibits both endo- and exopept idase activity but has no microbicidal effect. In model systems with pure c ultures of oral microorganisms, Krillase demonstrated inhibition of microbi al adhesion to saliva-coated hydroxyapatite. Furthermore, a protocol for th e growth of reproducible in vitro plaque films has been developed, and effe cts of Krillase on the plaque film were investigated by means of scanning e lectron microscopy (SEM). The results showed that Krillase efficiently rele ased microorganisms from plaque in vitro, the effect being dependent on the enzymatic activity. The surface energy of the substratum had a minor influ ence on the formation and removal of plaque in vitro. Ellipsometric studies on the formation and enzymatic removal of a salivary pellicle indicated th at the enzymatic effect on plaque may partly depend on degradation of the s alivary pellicle. Krillase was also able to remove plaque accumulated oil d entures in vivo. Our results demonstrate the potential or Krillase for plaq ue control, and that these enzymes are worthy of further investigations inc luding clinical studies and work to find a suitable vehicle.