Talk:Escherichia coli/Archive 1

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Role in digestion?

The article gives lots of examples of what E. coli can do, but doesn't actually say why E. coli is needed in the digestive process. Anyone up for adding a 'E. coli and digestion' section? --moof 11:30, 8 May 2006 (UTC)

In its current form the article mentions very little about the most common thing Escherichia coli does, helping in food digestion. It is mentioned that it is a necessary bacteria strain to have for proper digestion, but neglects to mention what it is that the bacteria actually does. Later on, it is mentioned that E. coli ferments lactose, but I think that's merely suggestive as I don't think they're the only thing that processes lactose in the human digestive system. I'd add to it myself, but microbiology is really not my area of expertise. --80.221.135.214 20:08, 9 May 2006 (UTC)

As far as I'm aware of (and I can be incredibly wrong here) E.coli's effect on digestion remains unknown. As of now it's certainly not considered as a "vital" part of the digestion anyway. --Selphiroth 09:01, 9 June 2006 (UTC)

From [1]-- "Escherichia coli is a common bacterium in the GI tract, but it is usually outnumbered by other types. E. coli is never a beneficial bacterium, but under normal circumstances the animal and E. coli tolerate each other." If anyone can find a reference to an important role played specifically by E. coli, please incorporate it into the article. It seems to me that there is no basis for calling it necessary for digestion, so I'm removing that claim from the article. Silarius 03:42, 28 September 2006 (UTC)

The byproducts of some intestinal bacteria are classified as vitamins, producing substances important to maintaining health. Vitamin K is such a substance, as are the B-vitamins. I've found references on the Web indicating that E. coli are involved in this process. As long as they're your own E. coli, the process works fine. When they're someone else's, you get violently ill. —Quicksilver^{T @} 19:46, 15 September 2006 (UTC)

Let's see the references, and have specific digestive roles detailed in the article, rather than a general claim that E. coli is necessary for digestion. Silarius 03:42, 28 September 2006 (UTC)

Also, it's not a matter of "your own" being safe and "someone else's" E. coli being harmful...it's the acid reisitant & toxigenic E. coli that's a problem, when you eat it. Silarius 03:42, 28 September 2006 (UTC)

I also want to know why even some 'harmless' e. coli are tolerated in the gut when they can so easily cause UTIs. They are not promoted to be a health food like classic yogurt acidophilus that are known to make vitamins. This example of commercial live culture yogurt contains eight beneficial strains: "S. THERMOPHILUS, L. BULGARICUS, L. ACIDOPHILUS, B. BIFIDUM, L. RHAMNOSUS, L. CASEI, B. LONGUM, B. INFANTIS" [2] Milo 23:21, 3 October 2006 (UTC)

Minor Changes

Just made a minor change. From what I understand, E. Coli toxins prevent absorption of water by the intestine, not the other way around. Worty

Old talk

Below is the text from three electronic flashcards I made from lecuture notes from two different microbiology classes. If nobody else is able to do so, I will translate this data into coherent English sentences as I find time. maveric149
Escherichia coli

1) Gram reaction? Gram -

2) Catalase reaction? Catalase +

3) Microscopic appearance? Rod

4) Colony characteristics? Colilert Test+ : yellow & fluoresce

5) Isolation? Fecal coliforms can grow @44.5°C,

inoculum?
media?
conditions?

Colilert Test: -ase = E. Coli enzyme

ONPG + ß-galactosidase ––> ONP(bright yellow) + G  
MUG + ß-D-glucuronidase ––> MU(fluoresces @340nm) + G

incubate 24 hrs @ 35°C

Colilert Test
ONPG Ortho-nitro-phenol-ß D-Galactopyronoside ß galactosidase is an enzyme of E. Coli that can cleave the bond between ONP & G in ONPG (this bond is similiar to the bond between Glucose & Galactose) MUG 4-methyl-umbelliferone-ß D-Glucuronide

Escherichia coli 1

1) Natural environment is ... large intestine of mammals

2) Dominant types are ... non pathogenic

3) Serology (# of Serogroups) = O (174), & H (flagellar, 56)

4) How many types are pathogenic.= 5 (3 are of most concern)

5) Ones that are of most concern
Enterotoxigenic E. coli (ETEC) ¹
Enteropathogenic E. coli (EPEC) ²
Enterohemorrhagic E. coli (EHEC)

¹ Major cause of death in 3rd world. Travelers & child diarrhea. Heat labile toxin & heat stable toxin.
² Cause of severe diarrhea in children & travelers.

Escherichia coli 2

1) How is O157:H7 different?
does not ferment sorbitol in 24hrs, MUG negative, doesn't grow well at 44-45°C, acid tolerant

2) Properties of EHEC?
>100 known serotypes (O157:H7), hemolytic uremic syndrome (HUS -- 3-5% deathrate), low dose, onset 3-8 days, sm intestine infector

3) Symptoms of O157:H7? Severe abdominal pain, bloody diarrhea, vomiting, low to no fever. Last 6-8 days. Produces shiga-like toxins (aka verotoxins)

Why was "Escherichia coli" moved here? We don't generally abbreviate genus/species names here; why do it in this case? --LDC

Because "Escherichia" is hardly ever used -- even by microbiologists (let alone everyone else). --mav

While it's certainly true that E. coli is an indicator species for fecal contamination of water, when we do surface water or treated wastewater sampling we are actually looking for total coliforms -- many species; occasionally also for fecal strep. There is some indication, though it's controversial, that the ratio of fecal coliforms to streptococci present can indicate whether the source is likely to be human (e.g., failing septic systems) vs. animal (e.g., agricultural runoff). When a drinking water utility reports a positive sample to us (e.g., contamination due to line break, etc.), presence or absence of E. coli is noted. Uyanga 14:44, 29 Aug 2003 (UTC)

Changes to text on E.coli and UTI

Just to explain the changes I've made to the para on UTI and E.coli. I've downgraded the importance of honeymoon cystitis a little. While intercourse can be a precipitating factor in UTI I don't think it's a major cause and may be largely aprocryphal. In practice there always 'seems' to be a large sex imbalance in the incidence of UTI (biased heavily to females) but as I understand it, over a lifetime the risk is about even. Male and female are equal up to age 10 or so, females then lead up to about 55/60 years (short urethra, pregnancy) then males suffer more (prostate, general aging, hospitalisation etc). I'll try to back this up with some figures if I can.

I'll try and add something about what makes E.coli (or at least some strains of E.coli) such good uropathogens as well, when I can.

Didn't sign that last contribution.Tim 21:12, 14 Nov 2004 (UTC)

from Journal of Gender Specific Medicine. 2000 Nov-Dec;3(8):27-34. (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11253265&dopt=Abstract) "Urinary tract infections (UTIs) are more common among women than men, although the prevalence in elderly men and women is similar." Matt 17:21, 26 May 2005 (UTC)

Presumably anal sex is a risk factor for females as well? Benwilson528

When you think about anatomy it makes sense that females will get more UTIs. UTIs are usually caused by bowel flora and it would be very easy for bugs to migrate from the anus to and up the very short urethra of females (~3 cm as opposed to ~20 cm in males), especially if hygiene is bad. Males don’t really get UTIs unless they’re infants (usually due to bad hygiene) or elderly (usually due to prostate hypertrophy preventing normal urine flow). Catheters also increase the risk of UTIs, and catheterization happens more in older people… UTI in a male who is not an infant or over 60 is so uncommon that in Australia if that’s what is diagnosed you have to check for structural abnormalities in the urinary system. --Queenvik 06:30, 13 April 2006 (UTC)

Recent Removal of reference

Recently an anonymous user has removed both the trivia and reference sections from this article. I was wondering what some people's reactions to this was/is. I was indifferent about the trivia section but believe strong references should be the corner stone to a great science section... anyone else have thought? Adenosine | Talk 03:40, August 21, 2005 (UTC)

I found a reference for the trivia, but I agree that its encyclopedicity is very limited. JFW | T@lk 09:28, 21 August 2005 (UTC)

Update "scientific classification" section?

Question: is someone willing to update the 'scientific classification' section? Describing bacteria as a 'kingdom' is outdated and misleading. I don't consider myself sufficiently qualified to correct it ... thanks --80.43.44.172 14:18, 9 October 2005 (UTC)

Pronunciation please?

Preferably IPA? —Keenan Pepper 21:57, 9 March 2006 (UTC)

I was about to ask the same thing. I found esh´´urik´Eu kO´lI, and know it's like "eh-shuh-RI-kee-uh CO-lie" or "eh-shur-I-kee-uh CO-lie" but can't translate it into the standard pronunciation.Dominicanpapi82 02:18, 24 May 2006 (UTC)

I added an IPA transcription. It's based on a pronunciation I found at http://www.kcom.edu/faculty/chamberlain/Website/studio.htm, and refined by posting to a linguistics community. Feel free to improve it. --71.229.140.55 13:57, 17 September 2006 (UTC) Tres

IPA is pretty near useless. Dominicanpapi82's pronunciation is wrong. So is the .wav file by Neal R. Chamberlain, Ph.D, linked by 71.229.140.55, though it's probably the best someone who never studied German or Latin can do.
You can get a clue from the spelling of the discoverer's name — Escherich. The phonetic pronunciation is closer to ESH-air-ish. The "ch" at the end is pronounced with the jaws spread slightly apart, the sides of the tongue wedged between the upper molars and tip not quite touching the front teeth, so one won't get the sharp "sh" sibilant sound. It's definitely not the "k" sound, nor is it the "tsh" sound that the letter combination "ch" represents in English. The "ia" suffix in Escherichia is like "ee-uh", as in the Latin phonetic pronunciation of the word via. So, putting it all together and shifting the emphasis to the correct syllable, it comes out as esh-air-I(SH)-ee-uh. If your tongue won't let you produce the German "ch" sound, you're better off using the English "sh" sound. Don't use the "k" sound; it'll make you sound like a hick.
Coli is pronounced "CO-lee"; it rhymes with "holy". If you pronounce the "li" at the end of coli as in "fly", you'll also sound like a hick. —Quicksilver^{T @} 09:39, 23 September 2006 (UTC)

It's too bad the enlish language doesn't have a soft g sound (or kh in the roman transliteration of semitic and cyrilic languages) ch in germanic languages is simply pronounced like a soft exhalation or an 'upward tongue' sigh. That is to say: position your mouth as if to make a 'ga' sound but instead of actually making a 'ga' sound, simply exhale. Also the 'a' at the end is pronounced as the 'a' in Patris or Amen without an american accent (as in 'In nomen Patris et Filius et Spiritus Sanctis, Amen'). 62.251.127.12 01:14, 13 April 2007 (UTC)

From what I understood of Hydrargyrum's/Quicksilver's post and what I know of German, sounds like it should be [ˌɛ.ʃəˈʁi.çja ˈkoː.li] (stresses?). Which, er, is completely different from what's in the article (-chia as [kjə], -li as [laɪ] rather than [li] as parent suggested). Someone care to verify/correct the pronunciation...? —Laogeodritt ^{[ Talk | Contribs ]} 19:21, 3 November 2007 (UTC)

External links

The link to http://3dscience.com/e_coli_ecoli_bateria.asp seems like kind of an advertisment.

survival/transport/conditions?

It would be interesting to know more about the conditions that reduce risk or increase risk (handwashing, etc), and what conditions favor survival or not (e.g., dryness, airborne dust, etc). For instance, see here. A section would be very welcome, from whoever is knowledgeable...Thank you!! --71.196.217.161 04:03, 19 September 2006 (UTC)

Dangerous strain of E. coli

According to US Department of Health and Human Services Centers for Disease Control and Prevention, the strain Escherichia coli O157:H7, one of hundreds of strains of the bacterium Escherichia coli., causes illness in humans. I am adding this early in the article. 70.176.232.214 04:51, 20 September 2006 (UTC)

For what it's worth, there is an entry on Escherichia coli O157:H7 already (mentioned in the main E. coli article further down), -- MarcoTolo 05:00, 23 September 2006 (UTC)

The CDC article doesn't go into details, but this strain may be an unintended byproduct of feedlots raising grain-fed beef cattle. The animals' digestive system is adapted to eating grass, not grain. A grain-heavy diet causes their lower digestive tract to become acidic, the environment in which E. coli O157:H7 evolved. As a result, it is sufficiently acid resistant to easily pass through the human stomach and make its way into the intestine, where its toxins can cause severe illness, organ failure and death. As this strain infests the intestines of cattle, it is excreted in their droppings and can make its way into surface and ground water supplies. If that water is subsequently used for irrigation of vegetable crops, e.g. spinach or lettuce, it can get into the human food supply. —Quicksilver^{T @} 05:04, 23 September 2006 (UTC)

Deer can also be a problem, according to this guy. Gzuckier 15:40, 25 September 2006 (UTC)

cleanup-organize

Although there's a terrific lot of information here, there tends to be a lot of random hopping badk and forth between topics, within each section. It could use reorg to address that. I did some. Gzuckier 15:41, 25 September 2006 (UTC)

Year that it was dicovered?

The article does state who discovered it, but not when.

Immunity?

If one often consumes dead e-coli, will they develop immunity over time?

Probably not, since there are zillions of them living in your gut already. Gzuckier 14:47, 22 November 2006 (UTC)

We also don't go in to anaphylaxis all the time from all those bacteria. Our gastro-intestinal tract is (fortunatly) very seperated from the rest of our body.. Adenosine | Talk 07:19, 23 November 2006 (UTC)

as normal gut flora there is no triggered immune response so we cannot develope a resitance or immunity to them. instead our guts innate immune defences include a mucose layer that prevents bacteria from reaching the actualy intestinal epithelium (actual intestinal cells). some other pathogens like salmonella and shigella can swim through this layer and as such cause disese. however the normal gut flora is there to assist in digestion and is kept in an eco system where its numbers and position are regulated.124.190.0.135 01:50, 22 August 2007 (UTC)

Outrageous numbers

I don't mean to use this page like a forum, but I'm assuming the recent E. Coli concerns will bring more traffic here. The claim that "The number of individual E. coli bacteria in the feces that a human excretes in one day averages between 100 billion and 10 trillion" is ridiculous. If E. Coli bacteria measures 1-2 micrometers in length and a tenth of that in diameter, then the daily amount excreted would be on the order of kilometers in size. I believe these numbers need to be examined or deleted. By the way, I'm not familiar with editing pages or the guidelines for them, so hopefully someone more able will do this. —The preceding unsigned comment was added by 74.67.34.13 (talk) 19:35, 8 December 2006 (UTC).

I got no opinion on the above, but I am just here to say that it's not uncommon to get 10^9 coli per ml in the lab; stuff looks like cream soup. So, probably, I'd guess the volume of 10^9 cells to be maybe half an ml; 100 billion would be about 50 ml, 10 trillion would be about 5,000 ml. Just a somewhat educated guess. Gzuckier 20:22, 8 December 2006 (UTC)

By my Calcs, the volume of 10 Trillion of the smaller quoted size of Ecoli, using the volume of a cylinder is 0.0785 ml. Please double check someone!!!

Just did a viable count giving me 4.5 x 10^9 cells per ml. I'm in the same ballpark as Gzuckier. The numbers may be a bit high but not outrageous.

Kingdom?

Anyone know what kingdom its in? The new bacteria catagories, like archaebacteria, or eubacteria? I forget, and the list skips right to phylum.

I'm pretty sure it's bacteria, or eubacteria, depending on which kingdom you look at. I know they're not archaea. delldot | talk 00:14, 4 January 2007 (UTC)

E. coli are definitely in Eubacteria, or Monera for older style taxonomy Adenosine ^talk 20:21, 5 January 2007 (UTC)

It is eubacteria, but this terminology is outdated and not used in modern textbooks^[1]. Eubacteria and Archeabacteria are now commonly called Bacteria and Archaea. Adding info to the page Paulyche 16:18, 8 January 2007 (UTC)

It's not a kingdom, it's a domain! 68.100.5.226 00:31, 14 February 2007 (UTC)

Citation Needed? ?Not it was already there

Some wag who knows how put a note that a citation was needed for the effectiveness of diclofenac, when they only had to read two lines down to seen the cite. Mazumdar_2006>Mazumdar K, Dutta N, Dastidar S, Motohashi N, Shirataki Y (2006). "Diclofenac in the management of E. coli urinary tract infections". In Vivo 20 (5): 613-9. PMID 17091768.

However, I belive it is needed at the place where it is states that bacterial conjugation was discovered because of E.Coli.

62.97.167.17 16:31, 28 February 2007 (UTC)

life cycle? replication time?

how long is their cycle? what is their time to replicate in vitro? what is their time to replicate in vivo? In immunocompromised individual? what about in a person with a "normal" immune system?

What is the word for the opposite of immunocompromised?

That would be immunocompetent. Fvasconcellos (t·c) 15:58, 15 July 2007 (UTC)

Most common name?

Wouldn't WP:COMMONNAME suggest this article be titled E. coli? Just curious. ~ UBeR 20:32, 20 May 2007 (UTC)

Never mind. It would be a dumb idea to do anyway (in my opinion), even if it is more common. ~ UBeR 07:40, 23 May 2007 (UTC)

Have to agree. As long as "E. Coli" redirects here, the full name is probably the best.--THobern 16:16, 10 June 2007 (UTC)

I absolutely agree. Very surprised to find the name of this article is the abbreviated form and not the full name (it has apparently been moved again to "E. coli"). Even though it is more commonly called "E. coli" in the media and in common usage (perhaps because the genus is a pretty horrendous-looking word), the article should be the full name. As a qualifier, compare with Methicillin-resistant Staphylococcus aureus - this is certainly more commonly abbreviated to MRSA in the media and in common use, but the article name writes it out in full. I think this is the way it should be. Leevclarke (talk) 22:33, 20 November 2007 (UTC)

On 13 July the page was moved to "E.Coli", but as per the above consensus, it has been moved back to Escherichia coli. Isopropyl 20:34, 13 July 2007 (UTC)

Gasoline Production

New article out about gasoline production using E.Coli -> http://www.technologyreview.com/Biztech/19128/

Clarify contamination sources

Would someone please clarify the article on how food contamination occurs? It talks about the presence of E. coli as if it were some natural thing that occurs on food. -Rolypolyman 13:42, 4 September 2007 (UTC)

Gram Negative Sporeforming Bacteria

In the introduction of this article, it mentions that gramn negative bacteria are unable to sporulate. Gram negative bacteria are, in fact, quite capable of forming spores. I'll leave it whoever wrote it to research and change it. —Preceding unsigned comment added by 24.226.63.224 (talk) 23:49, 1 October 2007 (UTC)

Conservation status???

In my opinion, the conservation status should be removed, as it is irrelevant for bacteria. Joeylawn 16:10, 2 November 2007 (UTC)