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How many cells are folding in an average humans body?

Posted: Mon Dec 03, 2007 4:01 am
by castlebomb44
How many cells are folding in an average humans body?

The other thing I was wondering about was that each WU is supposed to be a fraction of a second,... I was wondering how many computer would need to be running as fast as what was going on in that person.

Re: How many cells are folding in an average humans body?

Posted: Mon Dec 03, 2007 4:34 am
by sneakers55
castlebomb44 wrote:How many cells are folding in an average humans body?
Used the Google approach to research, found there are a number of estimates, from 10 trillion to 100 trillion.
castlebomb44 wrote:The other thing I was wondering about was that each WU is supposed to be a fraction of a second,... I was wondering how many computer would need to be running as fast as what was going on in that person.
IIRC, one F@H step is 0.2 femtoseconds.

A PS3 can do somewhere between 100 and 400 nanoseconds, depending on the complexity of the protein (and the ones that F@H runs on the PS3 aren't very complex).

Posted: Mon Dec 03, 2007 4:37 am
by bruce
Each cell in the body contain many different proteins. It's the proteins that fold.

Re: How many cells are folding in an average humans body?

Posted: Mon Dec 03, 2007 1:02 pm
by castlebomb44
IIRC, one F@H step is 0.2 femtoseconds.

A PS3 can do somewhere between 100 and 400 nanoseconds, depending on the complexity of the protein (and the ones that F@H runs on the PS3 aren't very complex).[/quote]

Wow, that is whole crap load of ps3s working at the same time.

Posted: Mon Dec 03, 2007 4:47 pm
by castlebomb44
I used 200 nanoseconds for the ps3 and I was going for how many ps3s it would take to do one work unit for one second and with my math I got 5 Million ps3s.

On a lighter note I have been folding on my ps3 almost 24/7 now.

Re: How many cells are folding in an average humans body?

Posted: Mon Dec 03, 2007 8:01 pm
by DanEnsign
sneakers55 wrote:
castlebomb44 wrote:How many cells are folding in an average humans body?
Used the Google approach to research, found there are a number of estimates, from 10 trillion to 100 trillion.
As far as I know, every cell in the human body (for that matter, every cell in every organism) is constantly generating thousands of protein molecules, every one of which has to fold into its functional form. Depending on the specific protein, folding either happens 'automatically,' with the protein molecules just collapsing to the functional form because of the laws of physics, or collapsing into nonfunctional forms which have to be guided into their functional forms by molecules (other proteins, in fact) called molecular chaperones.

One often wonders if molecular chaperones require molecular chaperones to fold. I think they probably do. I wonder if this means that your chaperone-requiring proteins were ultimately folded by your mother's molecular chaperones, back in the egg.

Dan

Re: How many cells are folding in an average humans body?

Posted: Mon Dec 03, 2007 8:31 pm
by Macaholic
DanEnsign wrote:I wonder if this means that your chaperone-requiring proteins were ultimately folded by your mother's molecular chaperones, back in the egg.
That's the best mother insult I've EVER heard! :lol: Just kiddin' Dan. Couldn't resist. :wink:

Re: How many cells are folding in an average humans body?

Posted: Sun Dec 30, 2007 2:17 am
by jheil
Ok, Protein folding overview: excuse me for the length

Proteins are a series of amino acids linked together by something called a peptide bond. All 20 amino acids have the same basic structure required to form the peptide bond (an amino group and a carboxylic acid group) and an R group. The R group is the important thing and it can vary in properties such as hydrophobicity (does it like water or not, or does it like oil etc), and acidity. The R group determines which amino acid it is.

A gene's DNA codes for an amino acid sequence. The amino acid sequence is realized through transcription to RNA then translation to the amino acid sequence itself (all of this is carried out by hundreds if not thousands of proteins). So the protein in its denatured (not folded) state is just a long chain of amino acids with these R groups sticking out. The thing is that the R groups can interact with each other and with the aqueous environment (water) around them. The amino acids that don't like water will be in the interior when the protein is folded, and the ones that do like water will be on the outside (most of the time). So, the protein can fold spontaneously due to all these forces within the protein and between the protein and the surroundings. Sometimes that is good enough for some proteins. However, other proteins need chaperon proteins, other compounds or specific pH in the environment to help with things like disulphide bond formation (important for structure of many human proteins).

If one amino acid in the chain is different this can have no effect if the substituted R group has similar qualities as the old one, or a big effect if the substituted R group is different and in the right spot to be of structural significance. If you made the exact same substitution somewhere else along the chain the effect could be totally different. It's ramifications are not apparent until structure is accounted for. For example: Sickle Cell Anemia. Sickle cell anemia is a genetic disease that causes red blood cells to carry oxygen poorly and get stuck in capillaries (not good). The affected cells look like a sickle instead of a circle. This is because the hemoglobin protein polymerizes (hemoglobins link together to form a chain). This arises from a change in amino acid in a specific position from glutamic acid to valine. The valine is more hydrophic, and it is on the outside in the structure, it doesn't like being there (it is energetically unfavourable). There is a nice little pocket on the other side of the hemoglobin that the valine fits in, so the next hemoglobin comes around and the valine finds the pocket. And, we have a hemoglobin chain and a sickle shaped cell that doesn't carry oxygen well.

So, structure is important and very hard to determine experimentally (via x-ray diffraction can take years for one protein). So Folding at Home is really quite a novel thing since simulating these processes in a computer is tough. Its analogous to a motion equation in physics (that can tell you where a ball will end up if you through it at 10 MPH at such and such an angle at such and such a time) but with a LOT more variables and variables that aren't as well understood. Experimentally determines structures are still way better than computational structures, but computational structures are getting better all the time.


I hope you found this relevant and maybe somewhat interesting.

John

Re: How many cells are folding in an average humans body?

Posted: Sun Dec 30, 2007 9:18 am
by Kakao
Yes, for me that was relevant and interesting. Thanks.

Re: How many cells are folding in an average humans body?

Posted: Sun Dec 30, 2007 7:34 pm
by MoneyGuyBK
good work jheil
Thanx

Peace

Re: How many cells are folding in an average humans body?

Posted: Thu Mar 13, 2008 2:22 am
by mikethemangler
As far as I know, every cell in the human body (for that matter, every cell in every organism) is constantly generating thousands of protein molecules,
What about Red Blood Cells? Aren't they just big bags of hemoglobin with no nucleus? No nucleus = no DNA = no transcription = no translation = no new protiens so wouldn't mature RBC's not have any folding going on?

Re: How many cells are folding in an average humans body?

Posted: Thu Mar 13, 2008 4:53 pm
by DanEnsign
mikethemangler wrote:
As far as I know, every cell in the human body (for that matter, every cell in every organism) is constantly generating thousands of protein molecules,
What about Red Blood Cells? Aren't they just big bags of hemoglobin with no nucleus? No nucleus = no DNA = no transcription = no translation = no new protiens so wouldn't mature RBC's not have any folding going on?
Is having no DNA the same thing as having no RNA or ribosomes? ;)

I'm not sure I know the answer, but my slightly educated guess is that RBCs still translate proteins.

Dan

Re: How many cells are folding in an average humans body?

Posted: Thu Mar 13, 2008 8:06 pm
by sneakers55
DanEnsign wrote:
mikethemangler wrote:
As far as I know, every cell in the human body (for that matter, every cell in every organism) is constantly generating thousands of protein molecules,
What about Red Blood Cells? Aren't they just big bags of hemoglobin with no nucleus? No nucleus = no DNA = no transcription = no translation = no new protiens so wouldn't mature RBC's not have any folding going on?
Is having no DNA the same thing as having no RNA or ribosomes? ;)

I'm not sure I know the answer, but my slightly educated guess is that RBCs still translate proteins.
Red blood cells have no detectable RNA (providing somebody didn't hack the article in Wikipedia :))

Re: How many cells are folding in an average humans body?

Posted: Thu Mar 13, 2008 8:24 pm
by DanEnsign
sneakers55 wrote:
DanEnsign wrote:Is having no DNA the same thing as having no RNA or ribosomes?
Red blood cells have no detectable RNA (providing somebody didn't hack the article in Wikipedia
I see Wikipedia says erythrocytes cannot synthesize RNA, but again, that's different than not having any. It's possible that RBCs are generated with mRNA and ribosomes; in this case they would synthesize proteins. On the other hand, I'm guessing.

D

Re: How many cells are folding in an average humans body?

Posted: Fri Mar 14, 2008 4:37 am
by mikethemangler
looks like I sparked a bit of a debate, so I decided to do some research and settle it. I went on AccessMedicine and searched for Erythrocyte. In Harper's Illustraded Biochemistry, 27th Edition, Section VI, Chapter 51 in the section titled: "Reticulocytes Are Active in Protein Synthesis" (I'd give a page # but I accessed it online) the first sentence says "The mature red blood cell cannot synthesize protein."

Sorry to contradict you. I just tend to look for exceptions to broad statements... annoying habbit I have :(.