Many Salmonella Typhimurium isolates share the same core genome, but differ in the repertoire of incurred prophages, and might therefore display different phenotypes. In this context, S. Typhimurium isolate D23580 belongs to a recently identified ST313 lineage of invasive non-typhoidal salmonellae (iNTS) isolated in Sub Saharan Africa, and harbors a novel BTP1 prophage which seems to be characteristic for this lineage. To study how this BTP1 prophage could potentially affect the behavior of its host, a plasmid-borne BTP1 shotgun library was constructed downstream of a conditional promoter, expressed in S. Typhimurium LT2, and screened for BTP1-borne factors able to affect the growth of this host. As such, a BTP1 locus could be discovered conferring a peculiar host lethality upon overexpression, with subsequent efforts aimed at dissecting the mechanism and potential impact of this toxicity.