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Text from a flashcard I wrote. Update article as needed. maveric149
Bacillus cereus Food Poisoning
1) Properties of B. cereus
2) Two types are....
3) Most US outbreaks are which type
4) Onset time of #3
5) Symptoms of #3
6) Toxin stability of #3
7) M.W. of toxin
8) Rabbit ileal loop test
5/07/01
1) Gram & catalase +, spore forming facultative anaerobic rod
2) staph-like & perfringens-like
3) staph-like (usually from fried rice)
4) 1-6 hrs
5) vomiting,nausea,diarrhea,cramps
6) heat stable
7) 5,000 (not antigenic)
8) negative
Bacteria of the genus Bacillus are Gram positive... I'm pretty sure Gram variable bacteria are the result of poor technique... Also, do you think B. cereus will grow on a media that is 7.5% salt (MSA)?
Bacillus cereus, and indeed the entire Bacillus genus is strictly Gram-positive. Maybe confusion arose from the fact that sometimes rod-shaped bacteria are described as bacilli regardless of their Gram staining. Regarding salt medium, 7.5% seems a bit high for B. cereus. But some of its relatives can grow on that ; for example in the lab we've got an Oceanobacillus that grows on high salt medium, up to 10 or 15% IIRC. IGollum 01:02, 15 June 2007 (UTC)[reply]
B. cereus definitely does not grow in 7.5% NaCl. In general, Staphylococci are the only common species that will grow in a salt concentration that high. Wikipedia has a good article on Mannitol Salt Agar which points this out; that medium is made with salt in order to be selective for staph. (Note that although B. cereus cannot ferment mannitol, it's the salt concentration that is relevant here, because MSA does contain other nutrients the species can survive on.) —Preceding unsigned comment added by 99.183.213.175 (talk) 06:16, 28 July 2009 (UTC)[reply]
Some suggestions for the development of this and related pages. First, we need to disambiguate the B. cereus sensu stricto species from the B. cereus group. This may require linking to a discussion of the definitions of bacterial species in light of horizontal gene transfer. B. cereus group species differ mainly by their plasmid content, and a few highly specific chromosomal differences, like the conserved point mutation in the plcR gene of B. anthracis.
Secondly, it should be made clear that the basic plasmid-less bug is an opportunistic pathogen that has an array of enterotoxins and so on, but it doesn't do much damage to healthy people. True pathogenicity is conferred in all cases by toxins on plasmids. Crystal toxins on pBtoxis etc. for B. thuringiensis, the tripartite anthrax toxin on pXO1 for B. anthracis. In B. cereus sensu stricto, it has been shown recently that emetic syndrome is caused by a toxin on a plasmid, pCERE01 (annoyingly, it has been given different names by two different groups), which has a lot of its sequence in common with pXO1 but with a different pathogenicity island. Periodontal isolates also possess distinct pXO1-like plasmids.
In addition, the conjugative plasmids and a few other mobile genetic elements should be evoked as they can be involved in the spread of virulence determinants and constitute a bit of a sore point for classification in the B. cereus family.
IGollum 01:17, 15 June 2007 (UTC)[reply]
So fried rice syndrome should be removed immediately. This is in reference to an isolated incident. That's like saying getting hit by a car is called 1998 Chevy Lumina Syndrome.
---Jon
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"Bacillus cereus is a facultative aerobe"... no such class for aerotollerance. maybe try facultative anaerobe.... —Preceding unsigned comment added by 71.143.153.250 (talk) 19:31, 6 April 2008 (UTC)[reply]
The article speaks only about "improper cooking", but does not say what might be "proper cooking".
Someone might think 100 °C is enough. [1]
Bork (talk) 14:03, 30 August 2008 (UTC)[reply]
Hey all! The doi on the following citation appears to be dead:
{{cite journal}}
: CS1 maint: DOI inactive as of January 2016 (link)So I went to follow-up and find the actual doi, but I can't find it anywhere. Actually I can't find the article online anywhere. Is anyone able to locate this? Maybe it only exists in print and as such has no doi? I hope someone else can solve the mystery. Thanks guys! Ajpolino (talk) 05:18, 7 February 2016 (UTC)[reply]
Is there scientific consensus around whether or not ingesting only spores (not vegetative cells) can cause foodborne illness? Some sources seem to suggest that germination in the small intestine is possible:
But others either dispute that germination is possible, or claim that spores are not present in food in adequate numbers to cause disease on their own. Moreover, most all food safety procedures focus on preventing germination and growth, not eliminating spores.
RickScott (talk) 15:20, 18 April 2020 (UTC)[reply]
[2] Reverting your "dubious". Ratel 🌼 (talk) 06:28, 19 April 2020 (UTC)[reply]In the gastrointestinal tract (small intestine), vegetative cells, ingested as viable cells or spores, produce and secrete a protein enterotoxin and induce a diarrheal syndrome, whereas emetic toxin, a plasmid-encoded cyclic peptide (cereulide), is produced in food products and ingested as a formed toxin.
[3]Although the presence of vegetative forms of B. cereus in food is always necessary for foodborne disease to occur...
[4] It doesn't sound to me like there's agreement that spores can germinate in sufficient number in the small intestine to cause foodborne illness, as the page currently implies. RickScott (talk) 15:35, 19 April 2020 (UTC)[reply]We did not find detectable amounts of vegetative cells in intestinal samples... Our results indicate that Bacillus is present in the intestinal tract solely as spores...
[5]Human intake of members of the B. cereus group can therefore either be deliberately intended, as is the case for probiotics, or nonintended through ingestion of food contaminated with residues of commercially applied or naturally occurring strains. In both cases, the cells are primarily ingested as spores. In food poisoning cases caused by B. cereus spores, the strains are believed to adhere to mucosal epithelium of the small intestine, and thereafter to germinate. The resulting vegetative cells produce enterotoxins responsible for diarrhoeal symptoms (Granum & Lund, 1997).
[6] (You'll have to google to get the full text).The mechanism of the diarrhoeal syndrome is believed to be as follows: food contaminated with B. cereus spores and/or vegetative cells is consumed. Spores pass through the stomach, reach the small intestine, germinate, grow, and thereby produce enterotoxins. Vegetative cells are believed to be very susceptible to stomach conditions, and will therefore hardly reach the small intestine
This article was the subject of a Wiki Education Foundation-supported course assignment, between 18 August 2022 and 5 December 2022. Further details are available on the course page. Student editor(s): Is73500, Anonymous microbe, Danimahoney, Jmoyang58 (article contribs). Peer reviewers: Aetilghman, Eecc27, Meghanherlitzka, Ragi02, Chinedu23, Nathalieslebreton, REL9040, Egross123, Bab35555, Dmancao7, Asherkhan5284.
— Assignment last updated by ICapt.NemoI (talk) 19:23, 19 October 2022 (UTC)[reply]