The Coxiella burnetii Dot/Icm System Delivers a Unique Repertoire of Type IV Effectors into Host Cells and Is Required for Intracellular Replication

• DOI: 10.1371/journal.ppat.1002056
• Publication Date: 2011-05-26T20:55:46Z
• Authors: Kimberly L. Carey; Hayley J. Newton; Anja Lührmann; Craig R. Roy
• Keywords: Coxiella burnetii

Coxiella burnetii, the causative agent of human Q fever, is an intracellular pathogen that replicates in acidified vacuole derived from host lysosomal network. This encodes a Dot/Icm type IV secretion system delivers bacterial proteins called effectors to cytosol. To identify new effector proteins, functionally analogous Legionella pneumophila was used genetic screen fragments C. burnetii genomic DNA when fused adenylate cyclase reporter were capable directing Dot/Icm-dependent translocation fusion protein into mammalian cells. identified unique having no overall sequence homology with L. effectors. A comparison genome sequences different isolates revealed diversity size and distribution genes encoding many these Studies examining localization function eukaryotic cells provided evidence several have affinity for specific organelles can disrupt cellular functions. The identification transposon insertion mutation disrupts dot/icm locus validate this apparatus essential Importantly, Dot/Icm-deficient mutant found be defective replication. Thus, data indicate subset translocated by apparatus, cumulative activities exerted enables successfully establish niche inside supports