what is listeria innocua? is it harmful to humans? does its presence
indicate bad sanitation?

Hi basha2,

Listeria innocua is a species of Listeria that can be found in food
proccessed under less than scrupulously clean conditions. While very
closely related to Listeria monocytogenes, L.innocua is not
pathogenic. (Causes no diseases)
Listeria (monocytogenes and innocua) organisms are found in soil,
water, sewage, and airborne in dust. Both monocytogenes and innocua
species genomes have been sequenced, and they are found to be very
similar. It?s taxonomy is such: Bacteria; Firmicutes; Bacilli;
Bacillales; Listeriaceae; Listeria.

Since the two species are so genetically similar, researchers may find
using the L.innocua species helpful in producing safer vaccines or in
the field of foodborne illness prevention. Genetic testing of the
bacteria can now differentiate between the dangerous L. monocytogenes
and innocuous L. innocua.

http://www.pasteur.fr/actu/presse/com/dossiers/GBgenomics/GBgenlist.html

http://www.pasteur.fr/actu/presse/press/Listeria.html

http://www.population.health.wa.gov.au/Environmental/Resources/Are%20hot%20chicken%20rolls%20safe%20to%20eat.pdf

http://www.vfu.cz/acta-vet/vol71/125-02.htm


?The genus Listeria includes 6 different species (L. monocytogenes, L.
ivanovii, L. innocua, L. welshimeri, L. seegligeri, and L. grayi).
Both L. ivanovii and L. monocytogenes are pathogenic for mice, but
only L. monocytogenes is consistently associated with human illness?
http://seafood.ucdavis.edu/HACCP/Compendium/Chapt15.htm

??L. innocua appears to be much more prevalent than L. monocytogenes
in most foods.?
University of Ulster
http://www.science.ulst.ac.uk/food/Listeria_Methods.htm

?Listeria are non spore-forming, nonbranching, Gram-positive rods that
occur individually or form short chains. Listeria are able to produce
adenosine triphosphate thorugh a complete respiratory chain, and have
several fermentation pathways. This coincides with their lifestyle as
microaerophilic, facultative anaerobes. Listeria are intecellular
pathogens that use host-produced actin filaments for motility within
the host cell. The bacteria propel themselves through the cytoplasm of
an infected cell using a tail composed of actin.?
http://biology.kenyon.edu/Microbial_Biorealm/bacteria/gram-positive/listeria/listeria.htm

?All listeria are psychrotrophic organisms, gram-positive,
nonsporeforming facultatively anaerobic rods.  In laymen's terms,
listeria is a light organism that moves through the air; it is
transparent with hair - like follicles.  Listeria organisms have the
ability to grow over a wide range of temperatures - from as low as 1o
F to as high as 113o F.  It exists in acidic environments, in the
absence of or at very low levels of O2 (oxygen), which enables it to
multiply in most environments.  It grows best in temperature ranges of
35o F to 40o F.?
http://www.iafalwaysfresh.com/listeria.html

?Listeria spp. is fairly common in the household and can be found in
47% of household supplies. Of this 47%, Listeria monocytogenes makes
up about 41% of this population. The highest percentage is found on
dishcloths and wash-up brushes, and so these areas need special
attention in the cleanup operation.?

http://ohioline.osu.edu/sc172/sc172_16.html

http://foodsafety.unl.edu/scripts/abstract.cgi?ID=992618306

Presence of Listeria in processed foods does indicate poor sanitation.
http://ethesis.helsinki.fi/julkaisut/ela/elint/vk/lunden/persiste.pdf


You can see on this chart that the incidence of L. innouca is more
prevalent than other species in this  meat packing plant:
http://www.sofht.co.uk/isfht/irish_99_listeria.htm

Food Safety: L. innouca and apples
http://www.ars.usda.gov/research/publications/Publications.htm?seq_no_115=149168

Hope this helps you! If any part of my answer is unclear, please
request an Answer Clarification, before rating. By doing so, I will be
able to assist you further, if possible.

Regards,
crabcakes

Search Terms:
Listeria innocua
Llisteria species

---

Request for Answer Clarification by basha2-ga on 17 Jan 2005 05:18 PST

crabcakes, should the presence of listeria innocua indicate a presence
of listeria monocytogenes?

---

Clarification of Answer by crabcakes-ga on 17 Jan 2005 08:01 PST

Hi there basha2,
  
  Listeria monocytogenes is a different bacteria than Listeria
innocua. They are in the same family, but different organisms.
Listeria innocua rarely causes illness, while Listeria monocytogenes
can and does,sometimes fatally, particularly in dairy products.

  If a food contains L. innocua, it will probably not sicken anyone. A
food *may* contain BOTH L. monocytogenes and L. innocua, but a lab can
easily distinguish the difference.

  Hope this helps!

Regards,
crabcakes