protein folding

[Zami'87]

I have some questions about chaperonins and protein folding...
1.How do chaperonins help folding the polypeptide chain(know about hydrogen bonds but mechanism...)? like enzyme?What's their origin? And did "first cell" contain genes for them?What if there would be a mutation and and some chaperonin would be nonfunctional? Would it be lethal?
How do polypeptide chains form protein with quaternary structure(are there also some helpers -exept chap.)?
Maybe sounded stupid but you can easily lost in details :oops:
Thanks in advance!

[RobJim]

Well, one of the basic ways that chaperonins work is to block other molecules from interacting with the folding protein. Some proteins have hydrophobic residues that might interact with similar hydrophobic residues on other proteins before the protein finishes folding. This causes aggregation of improperly folded proteins.

Did the 'first cell' have chaperonins? Possibly. In pre-biotic conditions there was almost certainly a complex evolutionary process occurring which acted on RNA and/or maybe other molecules. The existence of a full cell wasn't necessarily required for complex molecular interactions.

I am not familiar with chaperonins in general, but I'll look into it.

[Zami'87]

Originally Posted by RobJim

Well, one of the basic ways that chaperonins work is to block other molecules from interacting with the folding protein. Some proteins have hydrophobic residues that might interact with similar hydrophobic residues on other proteins before the protein finishes folding. This causes aggregation of improperly folded proteins.

Did the 'first cell' have chaperonins? Possibly. In pre-biotic conditions there was almost certainly a complex evolutionary process occurring which acted on RNA and/or maybe other molecules. The existence of a full cell wasn't necessarily required for complex molecular interactions.

I am not familiar with chaperonins in general, but I'll look into it.

Hi! Thanks! I did little search and I think that I understand mechanism now but still I didn't find answers to most of my questions
What's their origin? And did "first cell" contain genes for them?What if there would be a mutation and and some chaperonin would be nonfunctional? Would it be lethal?
You said that the first cell probably contained genes for them and I agree cause I read that ribosomes in prokaryotes don't have chaperonins function so it would be lethal for prokaryotes not to have them or to have a fatal mutation but I'm not sure for eukaryotes cause their ribosomes have that function...
so does that mean that most of mutations in genes for chaperones wouldn't be lethal?
And I read that mutation for hsp90 would be lethal in early embrionic stage....
Now do you know some diseases related to non functional chaperones?
ps most informations from http://www.chaperone.sote.hu/Examples.html
THANKS!
Jana

[RobJim]

A lot of your questions are moving out of the realm of chemistry and more into biology. They actually are questions I am highly interested in, but I don't think anyone knows the answers yet.

You might want to try this forum instead which is for biology topics:

http://www.biology-online.org/biology-forum/

You said that the first cell probably contained genes for them

No, I said possibly, not probably.

[phenics04]

Chk this out. This could help.
http://www.nature.com/horizon/proteinfo ... hartl.html

Cheers!

[adam00f]

the first cell did had genes but through eveloution the cell started getting more..how should i say this.advaced where u started seing strctures. but the first cell wasa bacteral cell with a strand of RNA..

that how i got it..lol


REgards,
Adam Zbucki