Characterization and transcriptional analysis of gene clusters for a type IV secretion machinery in human granulocytic and monocytic ehrlichiosis agents.

ABSTRACT: Anaplasma (Ehrlichia) phagocytophila and Ehrlichia chaffeensis, the etiologic agents of granulocytic and monocytic ehrlichioses, respectively, are obligatory intracellular bacteria that cause febrile systemic illness in humans. We identified and characterized clusters of genes for a type IV secretion machinery in these two bacteria, and analyzed their gene expression in cell culture and mammalian hosts. Eight virB and virD genes were found in each bacterial genome, and all of the genes were transcribed in cell culture. Although the gene order and orientation were similar to those found in other bacteria, the eight virB and virD genes were clustered at two separate loci in each genome. Five of the genes (virB8, virB9, virB10, virB11, and virD4) were located downstream from a ribA gene. Thes

SUBMITTER: Ohashi N 

PROVIDER: S-EPMC127848 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature