On 28 Jul 2002 14:19:20 -0000, claudia_azpilicueta at yahoo.com wrote:
>I work in Induced Systemic Resistance in bacteria of rhizosphere and I need to know in what form the bacteria conjugate the acid salicylic
>>>http://biowww.net/mynews/tree.php?group_name=bionet_microbiology&begin=0
See: 5,5'-Methylenebis, look at the structure at:
http://www.howstuffworks.com/aspirin1.htm.
Normally salicylic acid (levels from 0.1 to 1.0% and higher) kills
all kinds of bacteria, yeasts and molds, e.g., microorganism used in
the standard antimicrobial efficacy test (Title 21CFR). So, it acts
as an anti-microbial in itself. it is used in cosmetics as a
preservative and anti-acne medication all the time (Neutrogena
Corporation's products -- I was the senior research project manager
formulating these kind of products for them).
I don't know what kinds of rhizobacteria trigger ISR (actually SAR) by
producing salicylic acid or if there is anything special about the
form. Try looking in Pieterse et al., 1996, Van Wees et al., 1997,
and Pieterse and van Loon, 1999.
Have you tried a Google.com search? Here is what I found:
"In 1990, two groups discovered that salicylic acid accumulated in
infected plant leaves and, to a low level, in uninfected leaves (J.
Malamy et al., Science, 250:1002-4, 1990; J.P. Metraux et al.,
Science, 250:1004-6, 1990). Since salicylic acid was known to induce
SAR when sprayed on plants, scientists postulated that it was the
signal molecule that moved from infected leaves to uninfected leaves
to turn on systemic resistance. Subsequent studies reinforced this
notion of salicylic acid as a translocating signal."
--- DCE
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Background Information:
Induced Systemic Resistance (ISR) in plants is one of the projects I
worked on in 1977 (see my resume publication list
http://home.earthlink.net/~enigl/, "Induced Disease Resistance in
Plant,"-- it was also a plant communications and rudimentary plant
awareness / consciousness project. Much of this focused on the role
of ethylene in disease resistance, and "phytoalexins."
Plants can have a systemic broad-spectrum anti-pathogenic reaction
that is a kind of "acquired resistance" after an inoculation with a
pathogen (Systemic Acquired Resistance (SAR)). This is similar to
immunization in humans.
Another form of this ISR happens from bacteria associated
(symbiotically) with their roots. These are symbiotic bacteria in
that they are non-pathogenic to the plant (for the most part). These
are called "rhizobacteria" (see Van Loon's et al., 1998).
The bacteria I mostly worked with in 1977 were assumed to be
pseudomonads, gram-negative non-spore-forming non-fermentative, with
fluorescent pigment production, aerobic rods, now called "plant
growth-promoting rhizobacteria (PGPR). The fluorescent pigment
competes with pathogens for iron, so the action starts out as
"competitive inhibition" (this is my theory following Donald Orth's
theory). The PGPR bacteria may also provide the plant symbiotic
partner with iron as a growth true promoter (my theory), (see also,
Schippers et al., 1995, and Lipopolysaccharides of the outer membrane
of Pseudomonas fluorescens will give ISR -- Leeman et al., 1995).
--- Davin C. Enigl, Astromicrobiologist.
http://home.earthlink.net/~enigl
Non-Earthcentric AI Life Detection Project
(HACCP Validations)
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