Talk:Bacillus cereus

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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

[edit] Gram status

  • I've reverted the recent edits made by 192.203.222.78 regarding Gram status as I've been unable to find a source confirming B. cereus as Gram-variable—all of my texts says G+ve (as does my personal experience with Bacilllus strains). With a reputable source (i.e. one whose conclusion isn't drawn from technical errors like old cultures, poor technique, etc), I'm willing to talk.... MarcoTolo 20:21, 12 April 2006 (UTC)

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)

[edit] B. cereus group, toxins, virulence and plasmids

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)



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 _____________

"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)