OBJECTIVE LIFE SCIENCE
BIOCHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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are synthesized due to genetic mutations.
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are assembled by specialized bacterial enzymes.
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are formed by modification of standard side chain residues after the protein is synthesized.
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are toxic.
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are racemic.
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Detailed explanation-1: -Common modifications include phosphorylation, methylation, acetylation, amidation, formation of pyrrolidone carboxylic acid, isomerization, hydroxylation, sulfation, flavin-binding, cysteine oxidation and nitrosylation.
Detailed explanation-2: -Posttranslational modifications (PTMs) are covalent processing events that change the properties of a protein by proteolytic cleavage and adding a modifying group, such as acetyl, phosphoryl, glycosyl and methyl, to one or more amino acids (1).
Detailed explanation-3: -Each of the 20 amino acids has a specific side chain, known as an R group, that is also attached to the carbon. The R groups have a variety of shapes, sizes, charges, and reactivities. This allows amino acids to be grouped according to the chemical properties of their side chains.
Detailed explanation-4: -Protein phosphorylation is defined as a covalent addition of the phosphate group to the side chain of tyrosine, serine, and threonine amino acid residues.