Anti-bacterial compositions comparing lytic modified bacteriophage engineered to infect and kill different target bacteria

A composition comprising:

• (i) an anti-bacterially effective amount of at least one isolated modified lytic bacteriophage capable of infecting multiple different target bacteria, which at least one bacteriophage is modified to comprise:
• (a) a toxin gene encoding a toxin protein which is toxic to the target bacteria,
• wherein said toxin gene comprises an α/β small acid-soluble spore protein (SASP) gene, and
• (b) to express one or more host range determinant proteins which are not naturally present in the bacteriophage which confer multiple bacterial host specificities, wherein the host range determinant proteins comprise tail fibre proteins, and each tail fibre protein comprises a receptor binding region for binding to the target bacteria and a region linking the receptor binding region to the body of the bacteriophage;
• and
• (ii) a pharmaceutically acceptable carrier;
• wherein said composition is capable of inhibiting the growth of said target bacteria when administered to a subject infected with said target bacteria and/or when applied to an environment comprising said target bacteria.