First, and probably last, question from a newcomer - How many ribosomes (Jul/27/2006 )

I am a phycisist studying genetic regulatory networks. For the last couple of years I have ploughed through tons of biological literature, and now feel myself proudly approaching the level of 101 biologist. Pretty frequently, however, I have the necessity to ask some really basic questions which may knock a professional biologist out of his shoes. My question is this
(probably for a moderator, if any) : is this forum a right place to ask this kind of questions?
If not, that which site (group) would be more appropriate?

And now my first question just to test water:

Typically, how many ribosomes are there in a eukaryotic cell (yeast, C-elegan, human)? Dozens, hundreds, thousands, millions? Are they gene-specific or more or less universal in terms of the mRNA they translate?

Thank you,
Kamil Toth

Most of us have such basic questions on us.. but never manage to put them across.. and hence i vote for more such questions from Kamil.. what say Bioforum? Thanks!

Accoring to this article, ~ 5.5X10-5 per cell. however, the number changes as cell growth condition changes. http://www.pubmedcentral.gov/articlerender.fcgi?artid=221478

According to common knowledge, no, they are not gene specific.

Most of us probably forgot these numbers and we live/work happily without memorizing it. We can always use the wonderful Google search tool to find it within a few minute of time, such as what I just did.

5.5 multiplied by 10 to the 5th power...or 550000 I think this is what he meant

Kamil, you can always ask your question and quite likely you'll get answered, but it's also good to use the available tools at your disposal (i.e., google) to see if you can find it yourself. as genehunter said, that's not something we have memorized....except for maybe 5 minutes to pass a test in an early bio course

gee..ur physicist now into biology. u must be very good. well i always admire those people who have a background in physics and math then shifts to study biology..bec in the end they excel, often times better if not best. probably due to their good analytical skills.

hopefully that wont be ur last question.Keep the questions comin.

aimikin was right. During my search with Google, I also came across that bacteria E. Coli has about 1/10 of that amount at resting state. However, the number goes up many (80x?!, not exactly sure) folds at different growth condition. I think these numbers are not mean to be fixed at all time for a particular organism.

Although I prefer answering questions more related to experimental design, I dont mind looking up these facts for you if you are in need.

We are here to help each other.

Just a quick note: you didn't have to "order" the paper. All PubmedCentral papers (and many others) are full text online. You can download the PDF file from the linked site.

You might want to look at this paper, which examines the location of ribosomes in a small bacterial cell by tomographic reconstruction of tilted TEM images. It should appeal to your physics background.
J Struct Biol. 2006 Jun 3
Mapping 70S ribosomes in intact cells by cryoelectron tomography and pattern recognition.
Ortiz JO, Forster F, Kurner J, Linaroudis AA, Baumeister W. PMID: 16857386

Check out the section on searching the biological literature here:

http://openwetware.org/wiki/Searching_the_literature

Probably should have written that as 5.5 X 10^5 (or 550,000) per cell, to avoid confusion with 5.5 X 10^-5 (or 0.000055)...

Yes, indeed. Thanks for pointing it out.