Modified bacteriophage including an alpha/beta small acid-soluble spore protein (SASP) gene
Inventors
Fairhead, Heather • Wilkinson, Adam • Holme, Sarah • Pitts, Katy • Jackson, Alison
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-8697049-B2
Publication Date
2014-04-15
Expiration Date
Abstract
Provided is a modified bacteriophage capable of infecting a target bacterium, which bacteriophage includes an α/β small acid-soluble spore protein (SASP) gene encoding a SASP which is toxic to the target bacterium, wherein the SASP gene is under the control of a constitutive promoter which is foreign to the bacteriophage and the SASP gene.
Core Innovation
The invention relates to an isolated genetically modified bacteriophage that inhibits Staphylococcus aureus growth. The bacteriophage comprises an α/β small acid-soluble spore protein (SASP) gene encoding a SASP that is toxic to S. aureus, and the SASP gene is placed under control of a constitutive promoter foreign to the bacteriophage.
The modified bacteriophage is lysogenic and inactivates a lysis gene of the bacteriophage genome. The SASP gene is contained as a single copy functionally linked to the constitutive bacterial promoter, enabling production of toxic levels of SASP in S. aureus when present in multiple copies.
The document further describes a preference for non-lytic behavior by inactivating lysis functions, including by replacement of a holin gene. An example involving a φ11 variant is described, and testing shows SASP-dependent killing in S. aureus strain panels relevant to MRSA; superinfection immunity does not prevent SASP-mediated inhibition.
Claims Coverage
The document includes one independent claim directed to an isolated genetically modified lysogenic bacteriophage that inhibits Staphylococcus aureus growth, with four inventive features centered on foreign constitutive promoter-driven toxic SASP expression, lysis gene inactivation, single-copy SASP linkage, and selection from a defined bacteriophage group.
Foreign constitutive promoter driven toxic SASP expression
The bacteriophage inhibits Staphylococcus aureus growth and comprises an α/β small acid-soluble spore protein (SASP) gene encoding a SASP toxic to S. aureus, wherein the SASP gene is under control of a constitutive promoter foreign to the bacteriophage and drives production of toxic levels of SASP in S. aureus when present in multiple copies.
Lysogenic modified bacteriophage with lysis gene inactivation
The modified bacteriophage is lysogenic and contains a lysis gene of the bacteriophage genome inactivated.
Single-copy SASP gene functionally linked to constitutive bacterial promoter
The bacteriophage contains a single copy of the SASP gene functionally linked to said constitutive bacterial promoter.
Selected lysogenic bacteriophages for SASP delivery
The modified bacteriophage is selected from the group consisting of bacteriophage Twort, tIII-29S, ΦPVL, ΦPV83, φ11, φ12, φ13, φ542d, φ56812, K, P3, P14, UC18, 15, 17, 29, 42d, 47, 52, 53, 79, 80, 81, 83, 85, 93, 95, and 187.
Overall, claim coverage centers on a lysogenic genetically modified bacteriophage that inactivates a lysis gene and delivers a SASP gene expressed at toxic levels in S. aureus via a foreign constitutive promoter, with the SASP gene present as a single functional copy and the bacteriophage selected from the listed phage group.
Stated Advantages
Inhibits Staphylococcus aureus growth.
Provides SASP toxicity to S. aureus at toxic levels when expressed under a foreign constitutive promoter.
Enables lysogenic behavior through inactivation of a lysis gene of the bacteriophage genome.
Reports SASP-dependent killing in testing in S. aureus strain panels relevant to MRSA.
Superinfection immunity does not prevent SASP-mediated inhibition.
Documented Applications
Use as a modified bacteriophage to inhibit or prevent bacterial cell growth of Staphylococcus aureus, including S. aureus strain panels relevant to MRSA/CA-MRSA, as discussed via kill curve testing.
Interested in licensing this patent?