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12

The short summary is that typical TFs bind and read both strands together, as a basepair sequence. Some proteins instead recognise a site on the helix by its shape and flexibility. ssDNA-binding proteins obviously bind one strand but they do this in a non-specific manner. RNA-binding proteins recognise the sequence on a single strand by inserting ...


6

in silico modelling of anything in biology is an active field of research. It's very useful for making predictions and developing hypotheses, but any findings need to be confirmed experimentally. From the Folding@Home website: Folding@home has been a success. In 2000-2001, we folded several small and fast folding proteins with experimental validation ...


6

The answer is here, but depending on your level of comfort with the math I'm not sure how enlightening it will be. I think that the reason people tend to stick to one ligand/one receptor models is that they capture all the intuition without the tedious algebra. It's interesting that you are asking for the fraction of ligand bound to receptors ...


4

Are multi-chain proteins synthesized as one biological unit? Sometimes yes but mostly not. Some proteins are synthesized as one long polypeptide pre-protein which is cleaved by some proteases to yield multiple chains. After cleavage the intramolecular interactions become inter-molecular or inter-chain interactions. Insulin is a good example of this ...


4

A protein-protein interaction (PPI) binding site is a type of interface. If it has been established that the interface is a PPI binding site, then the terms can from that point forward be used interchangeably. But the word "interface" is very generic and does not have any specific scientific meaning so the nature of the interface must be defined or else the ...


3

What you need to do is compare the relative amounts of the protein in the insoluble (pellet) fraction to the soluble (supernatant) one. This way you can determine how soluble the RMAS has become through the effect of the indicated compound. DTT breaks disulfide bonds, but does nothing else to solublize the protein, so it's all in the pellet, with none ...


3

1) Is the attachment of zinc regarded as a type of post-translational modification? It is not really considered a post-translational modification because the zinc atom is not covalently bound to the protein. Binding to zinc is adsorption. 2) When carbonic anhydrase is denatured, is the zinc ion released in the medium? Yes, but it depends on ...


3

The short answer is that the Edman degradation is a multi-step process. The Wikipedia page has a decent picture of the mechanism. In practice, the peptide is reacted with phenylisothiocyanate (PTH) under mildly basic conditions to give a thiourea, which is stable. The excess PTH is separated from the thiourea intermediate. The thiourea is then treated with ...


2

Addition to the answer provided by Teige. Transcription factors bind to both the strands however your question also included proteins in general. DNA remains double stranded and twisted as helix most of the times; most proteins bind to both the strands as mentioned in the previous answer. However some proteins such as SSB (Single-strand binding protein) ...


2

Some experimental and modelling observations suggests, folding energy for right handed in more favorable. You can find more detailed answer to this question here.


2

This question is waaaay too broad, but I'll give some short and simplified answers to the hypothetical you asked at the end. First, let's reformulate your example a little bit: How does the ribosome move along a strand of RNA? How would it do it? By hydrolyzing GTP and somehow coupling the free energy associated with that reaction to forward motion. ...


1

First: You are right with your reasoning that Protein X (X) and Dcr-2 interact directly. Lets go through the blots: In the input you check for the proteins loaded into the setting and stain unspecifically with Coomassie. This part of the blot shows you no unspecific input, and both proteins of interest present. This also shows that Dcr-2 is much bigger than ...


1

As it seems with about everything in protein science, the answer is it depends on the protein. Many proteins will lose activity if they are truncated; however, I've worked with GPCR's that were truncated down to the extracellular portion only and they showed consistent kinetic results. Antibodies have been cut into pretty tiny chunks (scFv's) to create ...


1

As @canadianer mentions in his comment, Protein G is more than likely named after the human group G strain of Streptococci, G148. Protein G, a bacterial cell wall protein with affinity for immunoglobulin G (IgG), has been isolated from a human group G streptococcal strain (G148). Purification and some properties of streptococcal protein G, a novel ...


1

You are seeking a database of transcription factor binding specificities. Some model organism databases (which are manually curated), such as Wormbase contain some of this annotation. I suggest you search PubMed for papers by Tim Hughes at the University of Toronto. He has published extensively on this topic over the past 5 years. Papers he cites, and ...


1

As you can find under the table with cavity centers in pdf version of this article: The table lists the protein’s PDB ID, the ligand considered and the specified cavity center. 22 ligands are similar to hexoses in shape and/or size. The cavity center is the centroid of the reported PDB atom numbers. And a little later: The binding-site center is ...


1

I will try answer your question directly. How do we know if we fold it right? A. If you're interested in only the end product pf folding -- the 3D structure, then this is the subset of the folding problem called the structure prediction (from sequence alone). a. We can verify the structure experimentally by determining the 3D structures by NMR or ...


1

A certain fold of a peptide string can be validated or ruled out if other experimental data is available. Some other techniques to infer protein structure are X-ray crystallography (requires pure protein that will crystallize) and single particle analysis.



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