The present invention relates to methods of eliminating, reducing or preventing bacterial biofilms by means of a fusion protein comprising an endolysin, an autolysin or a bacteriocin to which a peptide with membrane or LPS disrupting activity is fused. Further, the present invention relates to fusion proteins for use as a medicament, in particular for the treatment or prevention of Gram-negative and/or Gram-positive bacterial infections associated with bacterial biofilm, as diagnostic means, disinfectant or as cosmetic substance. The present invention also relates to the removal or reduction or prevention of Gram-negative and/or Gram-positive bacterial contamination associated with bacterial biofilm of foodstuff, of food processing equipment, of food processing plants, of surfaces coming into contact with foodstuff, of medical devices, of surfaces in hospitals and surgeries. Furthermore, the present invention relates to the use of said fusion protein as a diagnostic means in medicinal, food or feed or environmental diagnostic associated with bacterial biofilm.