If proteins require chaperonins to fold properly, how do chaperonins fold themselves?
346976
The folding of proteins is inherent in its sequence of amino acids. The particular amino code sequence causes interactions among themselves due to charge difference. Chaperones only aid in folding by providing a neutral environment (safe zone) to fold away from the stressed state of the cytoplasm. Some chaperones are only expressed in times of stress, such as heat shock proteins. Chaperones themselves are folded into conformation through ATP/ enzymatic action. \nYou answer your own question...chaperonins fold themselves,due to their inherent sequence.
724174
packages them into vesicles
1115828
There are many factors that affect protein folding but most importantly it is dependent on the amino acid sequence. Different amino acid side chains (R groups) have different chemical characteristics. Folding occurs spontaneously through electrostatic interactions of these side chains (H-bonding and van der waals interactions) as well as disulfide bridges between cysteine aa's. Additionally it is entropically more favorable for hydrophobic parts of the protein to be in the center and the hydrophillic parts on the surface of the protein. Molecular chaparones also assist in protein folding.
838493
The answer to this question can be found in any biology text book or with a quick search inthe library or online, why dont you try thinking for yourself instead of demanding "proper and short answers" from other people who think for you. Or just accept what they tell you as it ans shorten it yourself?
386583
I know there are some proteins produced by prokaryotes and eukaryotes that lack a typical leader peptide sequence; for example lacking a hydrophobic leader peptide. Some of these proteins are exported to the membrane by a substrate specific ATP-driven membrane translocater. Used to be called ABC-transporters because they could bind and hydrolize ATP. I think T-cell presentation is associated with a system like this where ABC-transporters transport endogenous antigenic peptides to the ER where\nthey bind to the MHC: peptide receptor complex before being\ntransported to the cell surface. I know S. cerevisiae, MATa haploid cells, release a 12-residue posttranslationally modified lipopeptide that binds via a farnesyl\nmoiety attached via a thioether linkage to the C-terminal residue. So, basically I would suggest looking at a possible ABC-transporter or a lipopeptide. There might be other options but they escape me at the moment.
431813
Tag it with a poly ubiquitin chain.  You can make a chimera of the protein plus a couple of ubiquitins.  We did this for our protein (one ubiquitin tag at C terminus) and found it was degraded very efficiently.
342208
proteins are broken down to short chains of polypeptide in the stomach, which only takes about an hour after the protein is consumed.\n\nshort polypeptides are then broken down to amino acids in the small intestine. so the entire process should take no more than sevreal hours to complete.
95032
Cell has it own protective mechanism to distinguih self components from others .such methylation etc.. so that protease reconize self component and donot lyse it
943065
it will denature the protein
42608
That all depends on the enzyme. It could denature a protein involved, making the enzyme useless, or it could speed up the enzyme's activity.
843668
That would depend on the protein...Some proteins are needed in the nucleus (such as transcription factors), so they will go through their respective transporters into the nucleus. Other proteins need to get embedded in the cell membrane (such as receptors). Some proteins are enzymes and find other molecules to bind with and change...\n\nAlso, I forgot, most proteins go through post-translational modification (splicing, methylation, etc) before they are actually functional.
60612
Proteins are necessary in order for numerous vital functions of your body to happen.  Simply stated, without protein synthesis, you would die.  Proteins are necessary for the execution and regulation of nearly everything that happens in your body.
56873
The first answer is right on. But remember this as well: enzymes also have some ability to "buffer" the solution they are in as well! Because proteins (enzymes) have many chemical groups that can bind multiple hydrogen groups, its able to buffer to some extent. Generally speaking though, you'd need  a LOT of enzyme to really buffer a solution...so usually we don't worry about it!!
223793
It gets denatured. All enzymes have a working temperature range. Bolilng would definitely lead to denaturation.
180398
It varies depending whether you want the final product as an active protein or denatured.\n\nFrom cells\n\nHomogenisation\nCentrifugation (assuming you know what fraction the protein will be in)\n\nYou could then possibley use centrifugation across a glucose gradient that would further separate proteins or more simpley...\n\nFind a pH or temperature where the protein is insoluble. (Extremes will denature the protein)\nor...\nUse a size exclusion coloumn to filter out larger smaller proteins (depending on the coloumns specifications and your needs, won't denature).\n\nFor further purification:\n\nUse isoelectric focusing across a gel.\nUse a affinity chromatography coloumn specific to your protein.\n\nHope that helps. It's from memory and should be ok, I study biochemistry so if I've things wrong then I should be quite worried!
502057
"C" proteins is the correct answer.
828553
At physiological pH most of the -COOH of amino acids are deprotonated (-COO-) and -NH2 protonated (-NH3+).\nIf you increase the pH then the -COO- will remain as such but the -NH3+ will lose the proton. -NH3+ can act only as an H-donor for an H-bond so such a bond will be broken. However if the geometry and number of interacting partners allow it it could be replaced by another H of the same -NH2 group.\n\nTyrosine has pKa around 10, so if you go to extremely basic pH it will be deprotonated and thus it will not be able to act anymore as an H-donor for a hydrogen bond and the bond will break. If however it was acting as a lone pair donor, the bond will become even stronger.\n\nGenerally when the pH change (extremely basic or acidic) causes changes in the charge of the group can but not necessarily breaks H-bonds. An important note: even if the H-bonds are not completely broken there will be rearrangement (some bonds might break and others form as the some H-donors become H-acceptors and vice versa) changing the conformation/folding of the protein.\n\nFor sure the effect of pH on ionic bonds is far greater than that on H-bonds.