Ma. Schell, TO BE OR NOT TO BE - HOW PSEUDOMONAS-SOLANACEARUM DECIDES WHETHER OR NOT TO EXPRESS VIRULENCE GENES, European journal of plant pathology, 102(5), 1996, pp. 459-469
Pseudomonas solanacearum is a soil-borne phytopathogen that causes a l
ethal wilting disease of many plants, due in part to production of the
unusual exopolysaccharide EPS I and numerous extracellular proteins (
EXPs). Levels of EPS I and many EXPs are differentially controlled by
a complex sensory array whose size, organization, and other properties
set it apart from others found in prokaryotes. This network not only
controls reversible switching between two morphotypes, each probably s
pecialized for survival in different ecological niches (plant vs. soil
), but also fine tunes transcription of virulence genes in response to
multiple environmental signals. The interacting and cascading nature
of the network is reminiscent of a primitive neural network, apparentl
y designed to guide virulence gene expression during the dynamic inter
action of the pathogen with its environment. This minireview focuses o
n the unique aspects of the network and its regulated targets.