Chimaeric phages

摘要

A chimeric phage having a coat comprising a mixture of proteins. The mixture of proteins includes a fusion protein wherein a protein is fused to a functional form of a phage coat protein, and a mutant form of the phage coat protein characterized in that a phage having no wild type phage coat protein from which the mutant form is derived but having a coat comprising the mutant form and no copies of the functional form is less infectious than a phage comprising no wild type phage coat protein from which the mutant form is derived and having a coat comprising the mutant form and at least one copy of the functional form. Also, the associated phage collection comprising the chimaeric phage or an infectious phage containing at least one copy of a mutant form of a phage coat protein wherein the mutant form has lost the ability to mediate infection of a natural host by the infectious phage. Also a method for producing a phage particle. Also, a helper phage having a nucleic acid encoding phage proteins or functional equivalents for the assembly of the helper phage.