Type Three Secretion System in Pseudomonas savastanoi Pathovars: Does Timing Matter?
Pseudomonas savastanoi pv. savastanoi is the causal agent of Olive knot disease, relying on the Type Three Secretion System (TTSS) for its pathogenicity. In this regard, nothing was known about the two other pathovars belonging to this species, pv. nerii and pv. fraxini, characterized by a different host range. Here we report on the organization of the entire TTSS cluster on the three pathovars, and a phylogenetic analysis including the TTSS of those bacteria belonging to the P. syringae complex sequenced so far, highlighting the evolution of each operon (hrpC, hrpJ, hrpRS, hrpU and hrpZ). Moreover, by Real-Time PCR we analyzed the in vitro expression of four main TTSS genes, revealing different activation patterns in the three pathovars, hypothetically related to their diverse virulence behaviors.
Laboratorio di Patologia Vegetale Molecolare, Dipartimento di Biotecnologie Agrarie, Universitá degli Studi di Firenze, Via della Lastruccia 10, 50019 Sesto Fiorentino, Firenze, Italy. stefania.tegli@unifi.it.
Stefania
S
Tegli
Laboratorio di Patologia Vegetale Molecolare, Dipartimento di Biotecnologie Agrarie, Universitá degli Studi di Firenze, Via della Lastruccia 10, 50019 Sesto Fiorentino, Firenze, Italy.
Andrea
A
Gori
Laboratorio di Patologia Vegetale Molecolare, Dipartimento di Biotecnologie Agrarie, Universitá degli Studi di Firenze, Via della Lastruccia 10, 50019 Sesto Fiorentino, Firenze, Italy.
Matteo
M
Cerboneschi
Plant Protection Institute, Section of Bari, National Research Council (CNR), Via Amendola 122/D, 70126 Bari, Italy.
Maria Grazia
MG
Cipriani
Institute of Sciences of Food Production (ISPA), National Research Council (CNR), Via Amendola 122/O, 70126 Bari, Italy.
Angelo
A
Sisto