Streptomyces turgidiscabies Car8 contains a modular pathogenicity island that shares virulence genes with other actinobacterial plant pathogens

José C. Huguet-Tapia, Cornell University
Jonathan H. Badger, J. Craig Venter Institute
Rosemary Loria, Cornell University
Gregg S. Pettis, Louisiana State University

Abstract

Streptomyces turgidiscabies Car8 is an actinobacterium that causes the economically important disease potato scab. Pathogenesis in this species is associated with a mobile pathogenicity island (PAISt) that site specifically inserts into the bacA gene in Streptomyces spp. Here we provide the 674,223. bp sequence of PAISt, which consists of two non-overlapping modules of 105,364 and 568,859. bp. These modules are delimited by three copies of an 8. bp palindromic sequence (TTCATGAA), that also is the integration site (att) of the element. Putative tyrosine recombinase (IntSt) and excisionase (XisSt) proteins are encoded just upstream of att-R. PAISt has regions of synteny to pathogenic, symbiotic and saprophytic actinomycetes. The 105,364. bp PAISt module is identical to a genomic island in Streptomyces scabies 87-22, while the 568,859. bp module contains only a short region of synteny to that genome. However, both modules contain previously characterized and candidate virulence genes. © 2010 Elsevier Inc.