Metabolic products of pathogenic bacteria

Good Morning!

I'm attempting to provide the research for chemists devising a new method
for detecting pathogenic bacteria in food, and have what I thought would be
a simple question. However, after several days of intensive research, I have
not been able to put my finger on it, most likely due to my lack of working
knowledge in microbiology!

Would anyone be so kind as to inform me where I can find a list or database
(or ANYTHING!!) of the metabolites/products/gases/stuff exuded/given
off/produced by bacteria,specifically those involved in food poisoning and
food spoilage? I've located a database of metabolic pathways, but do not
have the background to determine which of the end-products would actually be
excreted by the cell into the environment.

I am grateful for any help that is offered!

---

"Jane Gonzales" <[Only registered users see links. ]> wrote in message
news:[Only registered users see links. ]...
be
have
working
database
be

Hi Jane

I really dont think you are going to be very lucky on this one unless you
can a find list of
exotic compounds ,characteristic and specific to the types of organisms you
have mention.

Im fairly familar with the metabolic products of most group II food borne
pathogens and nothing really stikes me as target
which might be usufull as an organism specific identifier in a food matirx.

Frankly I would be predict that detection or quatation by metabolite
production would be a very
unreliable technique for many reasons.

Firstly consider the example of Salmonella which may be present but capable
of infection in levels as
low as 10 cells per KG of food mateial !!!! You are not going ot detect
many metabolites from that level of contamination
and then ad the various factors of metabolic stress due to food processing
and things become more even difficult for you.

Pcr based systems would and do however detect such low low levels of
contamination with accuracy and rapidity.

Also unless you go for exotics my guess is that most food matrices will
contain a mozaic of microbial metabolites in
almost random patterns depending on the type of processing and various
factors relating to ingredients.

Also may metabolites are common to several genera and few are group
specific enough in isolation to
unqiuely identify a particular organism or even genus of organism.

Genreal metabolite detection and their effect on conductivity and
capacitance was the basis of Impdeance technique.

These were higly non specific and required elegant cultural situations to
produce
presumtive isolation of specific target organism..in other words cumbersome
and at best an interesting system for no specific pesudo quatation.


If you turn your attenion to toxin detection as an idndicator of specific
pathogenic contamination then you pressuppose
toxin is produce in all instanses of contamination which it is not.

I really dont want to pour water on your vison but the best tools we have
for rapid and accurate detection of food borne pathogens
todate focus around PCR and ELISA assay. Ememrging techquies invovle probes
tragetign cel wal structures and intra cellualr structures but
not metabolites.

Perhapes you could expand a little more on the proposed technique just in
case I havent fully understood the direction thi sresearch wil take.

Best N10

N10 wrote:


This is a database of genes that are sorted into biochemical pathways
that might be of some use... you'll have to browse around for a while
though, I think, to find anything that you might find useful, since it's
not really designed for this kind of thing. Anyhow, it has a lot of
pathways listed, so maybe it's of some help.

[Only registered users see links. ]

"Jane Gonzales" <[Only registered users see links. ]> wrote in message
news:[Only registered users see links. ]...

be
have
working
I hate to pour more cold water on the idea, but one potential problem I can
see (apart from the fact that you're dealing with a wide range of species,
all of which are different and which will produce different products
depending on the food) is that in food microbiology you rarely deal with
pure cultures, and most metabolic products will be seized upon with glee by
something else as a very desirable addition to the menu.....
And then, of course, there's the problem that much food poinoning is dure
to the fact that the bugs (eg E. coli) are themselves the dangerous item,
not their products.....
Lesley Robertson
[Only registered users see links. ]