Legionellashows a diverse secondary metabolism dependent on a broad spectrum Sfp-type phosphopantetheinyl transferase

Abstract

Several members of the genusLegionellacause Legionnaires’ disease, a potentially debilitating form of pneumonia. Studies frequently focus on the abundant number of virulence factors present in this genus. However, what is often overlooked is the role of secondary metabolites fromLegionella. Following whole genome sequencing, we assembled and annotated theLegionella parisiensisDSM 19216 genome. Together with 14 other members of theLegionella, we performed comparative genomics and analysed the secondary metabolite potential of each strain. We found thatLegionellacontains a huge variety of biosynthetic gene clusters (BGCs) that are potentially making a significant number of novel natural products with undefined function. Surprisingly, only a single Sfp-like phosphopantetheinyl transferase is found in allLegionellastrains analyzed that might be responsible for the activation of all carrier proteins in primary (fatty acid biosynthesis) and secondary metabolism (polyketide and non-ribosomal peptide synthesis). Using conserved active site motifs, we predict some novel compounds that are probably involved in cell-cell communication, differing to known communication systems. We identify several gene clusters, which may represent novel signaling mechanisms and demonstrate the natural product potential ofLegionella.