The draft genome of Staphylococcus warneri TRPF4, a bacteriocin producer with potent activity against the causative agent of Legionnaires' Disease.

In this work, we present the draft genome sequence of Staphylococcus warneri strain TRPF4 consisting of 2,634,550 bp with a G + C content of 32.4%. The genome sequence includes 2466 protein-coding genes, 11 rRNAs and 62 tRNAs, in 33 contigs. Applying the Rapid Annotation using Subsystem Technology (RAST) a total of 1322 protein-coding genes were assigned to 393 subsystems. Also, a set of 1286 protein-coding genes with designated functions were assigned to 21 categories in the Cluster of Orthologous Groups (COG) database. Further analysis of BAGEL3 software demonstrated that the TRPF4 genome contains two gene clusters responsible for the synthesis of three bacteriocins, one warnericin RK and two delta-lysins. Besides, a novel delta-lysin of 3.48 kDa was identified for the first time. The three predicted bacteriocins were chemically synthesized and screened for the antimicrobial activity against a range of pathogens, exhibiting a potent and specific antimicrobial activity counter to L. pneumophila, with minimum inhibitory concentrations (MIC) ranging from 1.9 to 7.8 µg mL-1. These results indicate that the strain TRPF4 can produce bacteriocins with anti-Legionella activity. This was verified by the extracting the bacteriocins from the fermentation broth and testing against L. pneumophila. Additionally, the strain TRPF4 exhibited no cytotoxicity in mammalian cell lines. In summary, the genomic sequences and in vitro assays demonstrated the potential application of bacteriocins from S. warneri TRPF4 as a scaffold for further development of drugs against L. pneumophila, the causative agent of Legionnaires' Disease. © King Abdulaziz City for Science and Technology 2020.