Questions tagged [proteins]
For questions about proteins. Proteins are biopolymers consisting primarily of polycondensated amino acids.
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Any cheap way to test whether a given powder has high protein content?
Protein powders are used as dietary supplements. The photo below is for whey protein powder, which usually has about 24 grams of protein per scoop:
Image: © jirkaejc/Getty Images
Unfortunately, many ...
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Do disulfide bonds determine the 3-dimensional structure of a protein or do they just stabilise the 3D structure?
I noticed that most disulfide bonds occur when two cysteine side chains exist in close proximity to each other. Do those cysteine side chains "look out" for each other during folding, that ...
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Histidine-Boc deprotectection
A question on Fmoc-solid phase peptide synthesis (SPPS). Is Boc-protected Histidine too labile? Merck's website shows Boc is labile to treatment with Piperidine. Anyone with such experience?
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How does one derive a KD from an equilibrium titration experiment? I am definitely making a mistake somewhere
Any help would be greatly appreciated. Thank you in advance.
If I have an antibody A and a target B, and experimentally titrate the antibody against a single concentration of B, and then measure the % ...
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What does the word "dynamics" mean in the context of proteins or biomolecules in general?
What does it mean by “dynamics” when we say “dynamics of protein” or “dynamics of biomolecules”? For instance, McCammon's paper has the title "Protein Dynamics" [1]. What does the word “...
user124269
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What are the available cheap proteins that are much less soluble than BSA
Currently, as a beginner, I'm performing solubility analysis (with UV based spectrometry) for practices.
The protein I'm using now is BSA. This is widely used and cheap option.
I'm now looking for a ...
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Can we compare absorbance of two peptides when the read concentration from Qubit Protein Assay are different?
I have two peptide A and B. And I would like to know the solubility level of these peptide in certain solute. For that purpose I use Qubit Protein Assay.
The Qubit readout I get is this:
Note that ...
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How to calculate concentration of a protein based on known concentration and mw of other protein
I have a Peptide A (mw = 5074Da), the table below showed
measured concentration by Qubit from 5uM up to 80uM solution.
All under 20uL solution.
Below is the standard plot for Peptide A (not sure if ...
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Why does a big protein move during gel electrophoresis but to a lesses extent through a size exclusion column?
A big protein going through gel electrophoresis will be forced through the gel, it will drift a small way and will show on the top of the gel, while in size exclusion, the big protein is not forced to ...
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Spectroscopic methods for quantifying peptides/proteins with or without Tryptophan or Tyrosine content
I have several peptides (20-50 amino acids long) which I want to quantify the solubility/concentration in a solvent at certain temperature and pH.
These peptides may or may not contain Tryptophan or ...
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How does protein denaturation speed change with temperature? [closed]
So this is something that I had been wondering since middle school. We "roughly" know that protein denaturation occurs above a temperature of 72 degrees Celsius, and is the reason why it is ...
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Is the 3D spacing arrangement of atoms in chemical bond always unique?
I would like to ask if the 3D spacing arrangement of atoms in chemical bond configurations are always unique, please?
For example, glycine consists of the set of atoms HHNCHHCOOH. Does there exist a ...
user120456
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Best description of forces/ mechanisms that stabilize the interaction between a hydrophobic protein binding pocket and a hydrophobic ligand
This is a more theoretical or definition question that is related to the terms "hydrophobic effect", "hydrophilic interaction", and "van der Waals' forces" (and others I ...
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How does ethanol separates salts from proteins [closed]
Grad student here messing around with famed TRIzol isolation protocol and looking to optimize the protein yield at the end. There are more direct ways to get protein from a sample but I like getting ...
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Troubleshooting an AutoDock Vina error on Chimera: “Could not find an atomic number for Hn Hn”
After minimizing a ligand (prepared with MarvinSketch) and preparing a target enzyme to dock said ligand onto (collected from RCSP PDB — 5DGN (Crystal structure of human FPPS in complex with compound ...
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