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What is the r/s configuration for D-alanine and L-alanine?
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+ Amino acids
+ Stereochemistry
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+ Organic chemistry
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Marco Pereira
What is the r/s configuration for D-alanine and L-alanine?
What is the r/s configuration for D-alanine and L-alanine?
All natural L-α-amino acids are (S) except cysteine.
The reason cysteine is an exception is because the sulfur atom in the side chain reverses the priority assignments of the four groups on the α-carbon.
Normally, the NH2 group is (1), the COOH is (2), the side chain is (3) and the H is (4). But in cysteine, the side chain has higher priority than the COOH group.
What is the r/s configuration for D-alanine and L-alanine?
All natural L-α-amino acids are (S) except cysteine.
The reason cysteine is an exception is because the sulfur atom in the side chain reverses the priority assignments of the four groups on the α-carbon.
Normally, the NH2 group is (1), the COOH is (2), the side chain is (3) and the H is (4). But in cysteine, the side chain has higher priority than the COOH group.
Well, alanine is … [math]H_{3}C-CH(NH_{2})C(=O)OH[/math] … And while I am no biochemist, alanine is LIKELY the zwitterion, [math]H_{3}C-CH(NH_{3}^{+})C(=O)O^{-}[/math], in aqueous solution…
And in strongly acidic solution, LIKELY we got the CATION …
[math]H_{3}C-CH(NH_{3}^{+})C(=O)OH[/math]. And thus one positive charge is associated with this species…
Well, alanine is … [math]H_{3}C-CH(NH_{2})C(=O)OH[/math] … And while I am no biochemist, alanine is LIKELY the zwitterion, [math]H_{3}C-CH(NH_{3}^{+})C(=O)O^{-}[/math], in aqueous solution…
And in strongly acidic solution, LIKELY we got the CATION …
[math]H_{3}C-CH(NH_{3}^{+})C(=O)OH[/math]. And thus one positive charge is associated with this species…
S&D is the common chemical nomenclature for asymetric carbons and it is perfectly correct to use it on biochemical molecules. But you might as well get chemist all the way and give the IUPAC name for alanine : acid 2-aminopropanoïc.
L&D is exactly the same thing and exists because biologists like to do things their way :-)
Then talking about S-alanine is not exactly wrong but mixes two different conventions : the biological one and the chemical one.
You'd rather choose between L-alanine and (S) acid 2-propanoïc, which are both correct and represent the same molecule.
S&D is the common chemical nomenclature for asymetric carbons and it is perfectly correct to use it on biochemical molecules. But you might as well get chemist all the way and give the IUPAC name for alanine : acid 2-aminopropanoïc.
L&D is exactly the same thing and exists because biologists like to do things their way :-)
Then talking about S-alanine is not exactly wrong but mixes two different conventions : the biological one and the chemical one.
You'd rather choose between L-alanine and (S) acid 2-propanoïc, which are both correct and represent the same molecule.
Alanine is an amino acid in which there is amino group(-NH2) connected to the benzene ring. Methyl alanine is alanine with 1 methyl group(-CH3) connected to it.
Alanine is an amino acid in which there is amino group(-NH2) connected to the benzene ring. Methyl alanine is alanine with 1 methyl group(-CH3) connected to it.
What is the r/s configuration for D-alanine and L-alanine?
All natural L-α-amino acids are (S) except cysteine.
The reason cysteine is an exception is because the sulfur atom in the side chain reverses the priority assignments of the four groups on the α-carbon.
Normally, the NH2 group is (1), the COOH is (2), the side chain is (3) and the H is (4). But in cysteine, the side chain has higher priority than the COOH group.
—C—S > —C—O
What is the r/s configuration for D-alanine and L-alanine?
All natural L-α-amino acids are (S) except cysteine.
The reason cysteine is an exception is because the sulfur atom in the side chain reverses the priority assignments of the four groups on the α-carbon.
Normally, the NH2 group is (1), the COOH is (2), the side chain is (3) and the H is (4). But in cysteine, the side chain has higher priority than the COOH group.
—C—S > —C—O
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Everywhere.
Alanine is one of the amino acids found in human proteins. It is found in practically all of the human proteins, so every human cell contains alanine.
Everywhere.
Alanine is one of the amino acids found in human proteins. It is found in practically all of the human proteins, so every human cell contains alanine.
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Transamination of alanine with alpha-ketoglutarate yields pyruvate (and glutamate ) Reduction of pyruvate yields lactate (lactic acid).
Transamination of alanine with alpha-ketoglutarate yields pyruvate (and glutamate ) Reduction of pyruvate yields lactate (lactic acid).
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Well, alanine is … [math]H_{3}C-CH(NH_{2})C(=O)OH[/math] … And while I am no biochemist, alanine is LIKELY the zwitterion, [math]H_{3}C-CH(NH_{3}^{+})C(=O)O^{-}[/math], in aqueous solution…
And in strongly acidic solution, LIKELY we got the CATION …
[math]H_{3}C-CH(NH_{3}^{+})C(=O)OH[/math]. And thus one positive charge is associated with this species…
Well, alanine is … [math]H_{3}C-CH(NH_{2})C(=O)OH[/math] … And while I am no biochemist, alanine is LIKELY the zwitterion, [math]H_{3}C-CH(NH_{3}^{+})C(=O)O^{-}[/math], in aqueous solution…
And in strongly acidic solution, LIKELY we got the CATION …
[math]H_{3}C-CH(NH_{3}^{+})C(=O)OH[/math]. And thus one positive charge is associated with this species…
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Empirical formula: C₃H₇NO₂
Molecular formula: H₃CCH(NH₂)CO(OH)
Structural formula: see the image in this article: Alanine - Wikipedia
Empirical formula: C₃H₇NO₂
Molecular formula: H₃CCH(NH₂)CO(OH)
Structural formula: see the image in this article: Alanine - Wikipedia
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S&D is the common chemical nomenclature for asymetric carbons and it is perfectly correct to use it on biochemical molecules. But you might as well get chemist all the way and give the IUPAC name for alanine : acid 2-aminopropanoïc.
L&D is exactly the same thing and exists because biologists like to do things their way :-)
Then talking about S-alanine is not exactly wrong but mixes two different conventions : the biological one and the chemical one.
You'd rather choose between L-alanine and (S) acid 2-propanoïc, which are both correct and represent the same molecule.
S&D is the common chemical nomenclature for asymetric carbons and it is perfectly correct to use it on biochemical molecules. But you might as well get chemist all the way and give the IUPAC name for alanine : acid 2-aminopropanoïc.
L&D is exactly the same thing and exists because biologists like to do things their way :-)
Then talking about S-alanine is not exactly wrong but mixes two different conventions : the biological one and the chemical one.
You'd rather choose between L-alanine and (S) acid 2-propanoïc, which are both correct and represent the same molecule.
More
VOTE
Alanine is an amino acid in which there is amino group(-NH2) connected to the benzene ring. Methyl alanine is alanine with 1 methyl group(-CH3) connected to it.
Alanine is an amino acid in which there is amino group(-NH2) connected to the benzene ring. Methyl alanine is alanine with 1 methyl group(-CH3) connected to it.
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