All Questions
Tagged with proteins organic-chemistry
47
questions
4
votes
3
answers
206
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How is it known that proteins are polymers of amino acids?
I read the following here.
In 1902, Emil Fischer and Frank Hofmeister independently proposed that proteins are formed from many amino acids, whereby bonds are formed between the amino group of one ...
- 109
2
votes
0
answers
25
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Reason for differences in AChE aging/reactivation kinetics between neutral and charged organophosphorus inhibitors
According to the referenced papers, acetylcholinesterase that has been inhibited by an organophosphate possessing thiocholine as its leaving group is more susceptible to reactivation by oxime ...
- 1,264
0
votes
1
answer
111
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Testing whether an unknown powder is wheat gluten (at home)?
Last week, I ordered wheat gluten to make seitan. I received some powder and attempted a recipe, which mixes 100g of water with 100g of gluten to form a sticky dough. However in my case, I only got a ...
- 109
2
votes
1
answer
88
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What can I do if a peptide won't go in solution in a biological assay?
I have working on the realisation of on assay, that is intended to examine the activity of a protein. The assay works in a way, in which the product of the target enzyme is transfered by a support ...
- 799
2
votes
0
answers
39
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How are enzyme inhibition constants assayed for "multi-inhibitors"?
Suppose there is a suicide inhibitor of an enzyme that reacts with the enzyme to form an inactive enzyme and another product. This "Another product", however, is capable of acting as a ...
- 1,264
2
votes
1
answer
92
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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 ...
1
vote
0
answers
31
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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 ...
- 1,264
1
vote
3
answers
407
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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 ...
- 67
0
votes
2
answers
567
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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 ...
-3
votes
1
answer
49
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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?
- 1
3
votes
1
answer
103
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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 ...
3
votes
0
answers
35
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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?
- 157
-4
votes
1
answer
468
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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 ...
7
votes
1
answer
159
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In solid-phase peptide synthesis, why are the formation of aspartimides a problem but not "glutamides"?
I'm studying solid-phase peptide synthesis (SPPS) at the moment, and a common problem is the formation of aspartimides, which disrupt the synthetic process.
I understand how they form and why are they ...
- 71
1
vote
0
answers
46
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Is there a computer program capable of showing protein conformational changes based on pH?
As it is known, changes in pH change the attractions between the groups in the side chains of the protein.
Acidification can, for example, cause protonation of the $\ce{COO-}$ end to $\ce{COOH},$ ...
- 111