Is
Pseudomonas syringae a friend or a
foe???
- Pseudomonas syringae
is a plant pathogen. This pathogen exhibits it’s
pathogenic traits by the characteristic of
biological ice nucleation. In the presence of the
ICE(+) gene P. syringae causes frost damage
on outer plant tissues which allows the nutrients of
tissues below to become
available for the metabolic
processes of P. syringae. This successful
nutrient acquisition
then allows for the growth of P. syringae, i.e. the
duplication of cells per binary fission.
- Strains of P. syringae
are known to infect a wide range of plant species
such as maple trees, cherry trees, beets, peas,
crabapples, species of grass, barley, tomatoes,
wheat, lilac trees, and wild beans. P. syringae
causes damage to
the plant hosts in a number of
ways. Currently, research is being done on P.
syringae as the cause of bacterial cankers on
Prunus avium L., otherwise known as sweet
cherries. To view more on this specific project
please see
- Because of P. syringae’s
close association with plants, particularly a number
of agriculturally produced plants, they are in turn
quite closely associated with us
, that is human
beings. As the world’s population is increases the
survival of crops is incredibly important both
economically and for survival. - Because of the
devastating effects this organism can have on crops
a number of methods for fighting this bacterium have
been studied. The most notable of these is the
discovery and the exploitation of the mutant ICE (-)
strains. This mutant has all of the same
characteristics as the ICE (+) strain except those
of ice nucleation. This means that, when introduced,
this organism can populate the same area as the ICE
(+) strains and compete for nutrients and space. For
more information about this check out
- For a look at a eukaryotic genetic mutation that had also benefited humans economically and agriculturally click here: http://bioweb.uwlax.edu/bio203/s2008/knudsen%5Fashl/ .
- For a look at a mutant in the domain bacteria that has played a negative role in human life click here: http://bioweb.uwlax.edu/bio203/s2007/allmann%5Fambe/ .
- Another notable plant
pathogen that is Eukaryotic and has also had a major
impact both historically and economically is
Phytophthora infestans. This
organism is the
cause of potato blight, the biological cause of the potato
famine of the 1840’s. More information on this
fungal plant pathogen is viewable at
- To see a cool video on the
kind of damage P. syringae can do to a plant
species click here:
- To see a cool video about how the
pathogenesis of a close relative of P. syringae
works click
here: