Bacteriophages
The present invention provides a bacteriophage with effective antibacterial activity against Staphylococcus strains and in particular MRSA. There is also provided a pharmaceutical composition comprising said bacteriophage and a method of treating a bacterial infection using a composition comprising said bacteriophage.
1. A Staphylococcus bacteriophage K mutant, which comprises one or more mutations within one or more of the following regions, corresponding to the nucleotide sequence of wild-type Staphylococcus bacteriophage K, selected from:
a) the region between ORF 18 and ORF 19; and/or
b) the region between ORF 41 and ORF 42; and/or
c) ORF 68; and/or
d) an overlapping region within ORF 86/88/90; and/or
e) ORF 92; and/or
f) ORF 93; and/or
g) ORF 96; and/or
h) ORF 100.
2. A bacteriophage according to claim 1 , wherein said mutation occurs within ORF 96 of the corresponding nucleotide sequence of wild-type Staphylococcus bacteriophage K.
3. A bacteriophage according to claim 2 , wherein said mutation is a C105975T point mutation of the corresponding nucleotide sequence of wild-type Staphylococcus bacteriophage K.
4. A bacteriophage according to claim 3 , which additionally comprises one or more of the following point mutations: C18554T, G40894A, G78197A, G99388C, G102111A, T103720C and/or A109329G of the corresponding nucleotide sequence of wild-type Staphylococcus bacteriophage K.
5. A bacteriophage according to claim 1 , wherein said mutation comprises one or more of the following point mutations: C18554T, G40894A, G78197A, G99388C, G102111A, T103720C, C105975T and A109329G of the corresponding nucleotide sequence of wild-type Staphylococcus bacteriophage K.
6. A bacteriophage according to claim 1 which additionally comprises a further mutation within the nucleotide sequence, wherein said further mutation comprises an insertion at position 116111 of the corresponding nucleotide sequence of wild-type Staphylococcus bacteriophage K.
7. A bacteriophage according to claim 6 , wherein said insertion is at least 9000 base pairs in length.
8. A bacteriophage according to claim 7 , wherein said insertion is 9547 base pairs in length.
9. A bacteriophage according to claim 1 , deposited under accession number: NCIMB 41894.
10. A pharmaceutical composition comprising the bacteriophage of claim 1 and a pharmaceutically acceptable carrier thereof.
11. A pharmaceutical composition according to claim 10 , which comprises an additional bacteriophage.
12. A pharmaceutical composition according to claim 11 , wherein the additional bacteriophage is P68.
13. A pharmaceutical composition according to claim 10 , wherein said pharmaceutical composition is formulated for topical application to the nasal cavity of a mammal.
14. A pharmaceutical composition according to claim 10 , wherein said bacteriophage is a pathogen of Staphylococcus aureus.
15. A pharmaceutical composition according to claim 14 , wherein said bacteriophage is a pathogen of Methicillin-resistant Staphylococcus aureus.
16. A method of treating a bacterial infection, comprising applying a composition according to claim 10 to an infected surface.
17. A method according to claim 16 , wherein said surface is the skin of a mammal.
18. A method according to claim 17 , wherein said surface is the mucosal lining within the nasal cavity of a mammal.