Altered intracellular targeting properties associated with mutations in the Legionella pneumophila dotA gene.

Legionella pneumophila dot mutations cause defects in intracellular targeting of the microorganism within cultured macrophages. Each of the previously characterized dot mutations was shown to be complemented by a single open reading frame designated dotA. The defects caused by the mutations appear to be due to disrupted function of the predicted 1048-amino-acid residue DotA protein, and not by polarity effects on a downstream gene. Complementation studies indicated that the product of the dotA53 mutation results in a partially functional DotA protein, consistent with a stable N-terminal fragment having biological activity.