confused about e. coli

[rakuenso]

This is too insignificant to be a post... but is e. coli a prokarya or an eukarya?

 

Does E. Coli have a mitochondria? If no, how ,where and if does the citric cycle take place?

 

Second, what do you call those bacteria...?

 

third, wth are mesosomes and how do they help respiration? is there a synonym of mesosome? also i read that mesosomes work only during aerobic conditions, but e. coli could survive w/o oxygen....

 

[Tommyknocker]

Well what is an E. Coli exactly? If it is a single celled organism, it is a prokaryote. Only eukaryotes have mitochondria (which some believe are prokaryotes in their own right) if that helps.

[Frostrunner]

Well E.Coli is a prokaryote and does not have any organelles (mitochondria, golgi, lysosomes, ect.). However the line between pro and eukaryotes gets blurry the closer you get to it. Yeast for instance has organelles but is single celled thus is it pro or eukaryotic. Also as mentioned in the previous post it is hypothesized that mitochondria originally was a single celled organism that became codependent on being inside another host cell. Once that happened some of the DNA from the Mitochondria was put into the nucleus and lost from the Mitochondria. As the Mitochondira became elvolutionarily tethered to the host cell it lost its "sense of cellness" and was forever coupled to the host cell. The Mitochondria as can be seen today still has a fair amount of DNA of its own still. Even today their can be seen in some bacteria a symbiotic relationship of internal bacteria with its own DNA. The internal bacteria becomes relient on the host and thus setting up the same relationships.

 

As far as the citric acid cylces goes, I don't know first hand but this paper looks like it will be good to answer your questions

http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6TD0-3WX1HP3-K-1&_cdi=5184&_orig=search&_coverDate=07%2F01%2F1999&_qd=1&_sk=999929992&view=c&wchp=dGLbVtb-zSkWA&_acct=C000006878&_version=1&_userid=86629&md5=ea50315211d5e7bad4d1ede83a437206&ie=f.pdf

To answer the Mesomes question look at the intro to this paper.

 

http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=249612&action=stream&blobtype=pdf

[Skye]

Karyon=kernel, and refers to the nucleus. Eu=true. So cells with a true nucleus, a membrane around their chromosomes, are eukaryotes. Those that don't have a nucleus are prokaryotes. E. coli is a prokaryote because it has no nucleus. Yeast have a nucleus, so they are eukaryotes. How many cells they have doesn't matter, although all the multicellular organisms are eukaryotes.

 

E. coli don't have mitochondria, so the TCA cycle occurs in the cytosol.

[Frostrunner]

Did they just drop the destinction of organelles vs no organelles? Also Maybe Skye can figure this out, I got to thinking and I know that there is a proton pump in the mitichondria for eukaryotes and I thought it played a part in TCA but how does the bacteria do it without this. Is it necessary? Sorry if is is elementry I haven't had TCA biochem in a long time.

[rakuenso]

hmm so mesosomes are like a weird version of the mitochondria

[Skye]

Did they just drop the destinction of organelles vs no organelles? Also Maybe Skye can figure this out, I got to thinking and I know that there is a proton pump in the mitichondria for eukaryotes and I thought it played a part in TCA but how does the bacteria do it without this. Is it necessary? Sorry if is is elementry I haven't had TCA biochem in a long time.

I just used the nucleus to seperate them because it's the easiest to remember, because that's what they are named after.

 

E. coli has the ATPase proton pump, but it is embedded in their cell membrane. This is equivalent to the set up in the mitochondria, in line with the endosymbiosis theory.

[Tommyknocker]

I think the one thing that definately separates eukaryotes and prokaryotes is the existance of a nucleus... as like someone said, that's what these names imply.

 

prokaryote- before nucleus

eukaryote- something nucleus (I forget lol, but it's something along the lines of 'has a necleus' )

[owertail]

IS E.COLI A CELL ORGANELLE OR A CELL??? IDK THE ANSWER PLS ANSWER THIS QUESTION QUICK ASSIGNMENT >.<