Supersize me: Cronobacter sakazakii phage GAP32

摘要: Cronobacter sakazakii is a Gram-negative pathogen found in milk-based formulae that causes infant meningitis. Bacteriophages have been proposed to control bacterial pathogens; however, comprehensive knowledge about phage required ensure its safety before clinical application. We characterized C. vB_CsaM_GAP32 (GAP32), which possesses the second largest sequenced genome (358,663bp). A total of 571 genes including 545 protein coding sequences and 26 tRNAs were identified, thus more than smallest bacterium, Mycoplasma genitalium G37. BLASTP HHpred searches, together with proteomic analyses reveal only 23.9% putative proteins defined functions. Some unique features this include: chromosome condensation protein, two copies large subunit terminase, predicted signal-arrest-release lysin; an RpoD-like possibly involved switch from immediate early delayed transcription. Its closest relatives are all extremely myoviruses, namely coliphage PBECO4 Klebsiella vB_KleM-RaK2, whom it shares approximately 44% homologous proteins. Since homologs not evenly distributed, we propose these three phages belong new subfamily.