All Questions
Tagged with proteins amino-acids
24
questions
2
votes
0
answers
103
views
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 ...
- 161
0
votes
2
answers
567
views
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
5
votes
0
answers
70
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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 ...
- 107
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
-3
votes
1
answer
134
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Hypothetical Alternative for Nitrogen [closed]
Recently I was surfing the internet and I found thisWikipedia article.
It states that
The element silicon has been much discussed as a hypothetical alternative to carbon. Silicon is in the same group ...
- 105
0
votes
1
answer
199
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How can all amino acids point outwards from an alpha helix, if peptides are mostly trans?
My textbook in biochemistry ("Biochemistry" - Berg,Tymoczom Gatto, Stryer) tells me that:
"Almost all peptide bonds in proteins are trans" (p. 40)
At the same time, it states the ...
- 161
-2
votes
1
answer
122
views
What does the following diagram represent?
Suppose, the following is a diagram of a protein's polypeptide chain:
What does this diagram represent?
What are the letters A, E, M, W, L, N, S, etc. represent? (I suppose these are amino acid ...
user93950
0
votes
1
answer
298
views
Carbon atoms types in amino-acids [closed]
I'm looking for a table or another kind of schema where I can find which type of carbon atoms (sp3, sp2 etc.) are present in each amino-acid.
In my biochemistry books these informations are not ...
- 293
1
vote
1
answer
250
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Depicting a mechanism of peptide bond formation with protonated and deprotonated amino group
I've noticed that some textbooks and video lectures use an amino acid wherein the amino group has two hydrogens, and others use an amino acid with three hydrogens in the amino group (in the formation ...
- 39
2
votes
0
answers
87
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Which amino acids can be totally synthesized? [closed]
I can't find information regarding which amino acids (say the proteinogenic ones or in general) can be totally synthesized. Is there a reference?
- 37
2
votes
0
answers
1k
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Why is it rational that salt-bridges (in proteins) are described as a combination of H-bond and ionic bond?
This is a fundamental question that came to me as I was trying to draw the electrostatic attraction between Aspartate (D) and lysine (K). I have always considered the charge on nitrogen, in the lysine ...
- 918
0
votes
1
answer
775
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How to tell the difference between lysine and the N-terminal amino acid in DNP labeling?
The N-terminal amino acid of a protein can be identified by reacting the N-terminal amine with FDNB (1-fluoro-2,4-dinitrobenzene), or Dansyl chloride, or Dabsyl chloride, then digesting the protein ...
- 2,228
1
vote
1
answer
733
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Acid-Temperature coagulation of milk
I was making coffee with a cup of boiling milk which was 2 days old. I used instant coffee powder and some sugar for the making of it. Tried to make a very hot coffee but usually prefer medium hotness....
-1
votes
2
answers
101
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Does water in big cities get heated (boiled) for treatment?
I live in Bangkok and read how water comes to customers here:
I understand from the chart that water go through Thon Buri treatment plant (west Bangkok) and Mahasawat treatment plant (east Bangkok) ...
user61828