OBJECTIVE LIFE SCIENCE
BIOCHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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they are chiral.
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they turn polarized light to the left.
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they have a configuration of groups around the C
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they are all (S)-amino acids.
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they are all (R)-amino acids.
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Detailed explanation-1: -Enzymatic Conversion of L-Amino Acids. As L-amino acids are present more predominantly in living organisms, they act as a substrate for D-amino acid synthesis. This conversion reaction occurs in the presence of the enzyme racemase, which changes the stereochemistry of the chiral -carbon in these amino acids [4].
Detailed explanation-2: -Although the ribosome catalyzes protein synthesis using more than 20 chemically diverse natural amino acids, these natural amino acids are all of L-or achiral configurations.
Detailed explanation-3: -All amino acids except for glycine are stereoisomers. This means that there are mirror images of their structure. It is just like how we have left hands and right hands. These are labeled L (left-handed) and D (right-handed) to distinguish the mirror images.
Detailed explanation-4: -To determine if an amino acid is L or D, look at the carbon, so that the hydrogen atom is directly behind it. This should place the three other functional groups in a circle. Follow from COOH to R to NH2, or CORN. If this is in a counterclockwise direction, the the amino acid is in the L-isomer.