Pseudomonas syringae pv. syringae (Pss) (Pss)

Pseudomonas syringae pv. syringae (Pss) is a Gram-negative, aerobic bacterium that serves as a significant plant pathogen with an exceptionally broad host range, including woody and herbaceous plants (Young, 1991). It is distinguished from other pathovars by its production of the lipodepsipeptide toxins syringomycin and syringopeptin, which form pores in host plasma membranes to induce nutrient leakage and cell death (Hutchison and Gross, 1997). A key feature of Pss is its ice nucleation activity, mediated by specialized surface proteins that catalyze ice crystal formation at temperatures just below freezing, thereby causing frost injury that facilitates bacterial entry (Lindow, 1983). In agricultural settings, Pss is the causative agent of diseases such as bacterial canker of stone fruits and bacterial brown spot of beans (Kennelly et al., 2007). Control measures typically involve the application of copper-based bactericides or antibiotics like streptomycin, although the emergence of resistant strains poses a significant challenge to disease management (Sundin, 2002). Because Pss is a whole organism rather than a specific protein or receptor, it is classified as a biological target for antimicrobial therapy rather than a molecular target.

Other names

P. syringae pv. syringaePseudomonas syringae pathovar syringaeBacterium syringae

Inhibition of the 30S ribosomal subunit to prevent protein synthesis (streptomycin); induction of oxidative stress and non-specific protein denaturation (copper ions) (Sundin, 2002).