Questions tagged [proteins]
For questions about proteins. Proteins are biopolymers consisting primarily of polycondensated amino acids.
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By what mechanism does amylase catalyze hydrolysis?
I've recently been learning bits and pieces of starch metabolism, and am wondering if anyone could explain exactly what is going on when alpha or beta amylase "cleaves" the 1-4 glycosidic ...
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Does the word "restraint" have any special meaning in the case of protein or biochemistry?
The following screenshot is taken from the book The Encyclopedia of Physical Science & Technology, volume: Biochemistry, Edition: 3rd, Page-197.
The text says:
FIGURE 3 Schematic representation ...
user124269
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Is there any special meaning to the angle between two peptide planes?
Take a look at the following image:
Is there any special meaning to the angle between two peptide planes (marked with red arrow heads)?
If so, why isn't a specific name (like phi, psi, etc.) given?
user124269
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Why is AChE inhibited by triflates not susceptible to reactivation?
According to a report, certain esters of trifluoromethanesulfonic acid are capable of acting as irreversible inhibitors of acetylcholinesterase. Also, 3-PAM, while capable of reactivating AChE ...
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Is it possible to replace 3-mercaptopropionic acid with 2-mercaptoethanol to solubilize avian eggshell membrane to soluble eggshell membrane protein?
Is it possible to replace 3-mercaptopropionic acid with 2-mercaptoethanol to solubilize avian eggshell membrane (ESM) to soluble eggshell membrane protein (SEP)?
Most literature suggested the use of ...
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Protein/polypeptide nomenclature, residue number superscripted or not?
When referring to a specific residue number of a given amino acid, should the residue number be superscripted or simply affixed?
For example, When referring to a Tryptophan residue at the 147th ...
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Do whey proteins precipitate with heat?
I am currently studying about the biochemistry of yoghurt and when reading about the effect of heat in milk proteins specifically whey, my book says that heat can denature whey proteins.
So after the ...
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How come in biuret test the copper sulfate doesn't react with the sodium hydroxide?
As I understand the color change in the biuret test is due to the formation of a complex between the peptide (with more than 2 peptide bonds) and the $\ce{Cu^2+}$ ion, from $\ce{CuSO4}$. But before ...
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Why is collagen fibre autofluorescent?
Why is collagen fibre autofluorescent? Proteins with increased amount of trp, tyr, phe tend to fluoresce but I don't think collagen fibre has increased percentage of any of them. Some say collagen ...
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Why do hydrogen bonds between atoms of the polypeptide backbone, form both helix and pleated structures, instead of only one structural type?
Proteins have segments of their polypeptide chain/chains that can be repeatedly coiled or folded into helix and pleated structures, respectively. This is due to hydrogen bonds between partially ...
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Why are proteins made up of alpha amino acids and not beta amino acids?
Why are proteins made up of alpha amino acids and not beta amino acids? Or gamma amino acids? My idea on this would be that a world with beta or gamma amino acids would be too complicated? Is that ...
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what is the meaning by 'species' of glycine? [closed]
The question ask for the species of the (i) glycine hydrochloride (ii) glycine titrated with NaOH. When they mentioned 'species', what did they mean by it?
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How to calculate absolute charge of a protein [closed]
My understanding is that hydrogen bonds formed by proteins require the NH2 / COOH to be neutral. Hence to find out when the hydrogen bonds are the strongest will depend on the absolute charge of the ...
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How is geometry optimization of small molecules different from the protein folding problem?
My layman's understanding is that finding the ground state geometry of small molecules is "hard". I don't have a good sense of how hard though. I suppose there are applications where methods ...
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Contaminants in Ion Exchange Chromatography significance?
I am a high school senior and decided to do a project on the essential amino acid composition of varying vegan protein mixtures. I have run into a problem concerning protein purification. One of the ...
