CHARACTERIZATION OF PD0528: A POTENTIAL TYPE V AUTOTRANSPORTER IN THE XYLELLA FASTIDIOSA OUTER MEMBRANE

• Author(s): Igo, Michele; Kirkpatrick, Bruce; Matsumoto, Ayumi;
• Abstract: Autotransporters are multi-domain proteins that are responsible for secreting a single specific polypeptide (the passenger domain) across the outer membrane of Gram-negative bacteria. Here, we report our studies on the putative autotransporter protein PD0528. The passenger domain of PD0528 contains six tandem repeats of a 50-60 amino acid motif that is found only in Xf species. To determine the role of these species-specific tandem repeats in Xf virulence, we have begun a detailed characterization of PD0528. Using primer extension analysis, we have located the transcriptional start-site of the PD0528 mRNA. We have also generated a deletion mutation in PD0528 and shown that the PD0528 protein is not present in the outer membrane of this mutant strain. Finally, we have examined the in vitro phenotype of the PD0528 deletion mutant. This analysis suggests that the absence of PD0528 in the outer membrane has a profound effect on Xf colony morphology and in the ability of this mutant to form cell-to-cell aggregates in liquid culture.
• Publication Date: Dec 2005
• Journal: 2005 Pierce's Disease Research Symposium