Microarray profiling of host-extract-induced genes and characterization of the type VI secretion cluster in the potato pathogen Pectobacterium atrosepticum

• DOI: 10.1099/mic.0.2008/017582-0
• Publication Date: 2008-07-30T17:52:27Z
• Authors: Laura Mattinen; Panu Somervuo; Johanna Nykyri; Riitta Nissinen; Petri Kouvonen; Garry Corthals; Petri Auvinen; Marja Aittamaa; Jari P. T. Valkonen; Minna Pirhonen
• Keywords: Pectobacterium; Gene cluster

Pectobacterium atrosepticum is a Gram-negative plant-pathogenic bacterium that rots potato stems and tubers. Microarray analysis was used to identify genes were differentially expressed when host extracts added the growth medium. Potato downregulated expression of ribosomal related uptake metabolism nutrients, upregulated needed for nitrate or phosphonate use. Some observed changes in gene host-extract-induced cultures are similar those during attachment tissues. Other responses indicated defence against toxic metabolites extract. Tuber extract induced large cluster having homology type VI secretion shown be virulence determinants many, but not all, animal human pathogens. Two found infection tubers stems, mutants with knockouts corresponding had increased on potato. One further characterized grow higher cell density culture presence produce slightly more extracellular tissue-macerating enzymes than wild-type strain. Analysis secreted proteins showed this mutant affected production haemolysin-coregulated (Hcps), which have been suggested by pathway other bacteria. The results suggest system P. Hcps its plant,