25. Protein and Amino Acid Metabolism

Name the reaction that removes nitrogen from an α-amino acid, forming an α-keto acid.

What amino acid yields the following α-keto acid through transamination?

Draw α-keto acid produced by transamination of glutamine.

What is the structure of the α-keto acid formed by transamination of the amino acid phenylalanine (Phe)?

Unlike most amino acids, branched-chain amino acids are broken down in tissues other than the liver. Using Table 18.3, identify the three amino acids with branched-chain R groups. For any one of these amino acids, write the equation for its transamination.

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What is the structure of the ⍺-keto acid formed from transamination of the following amino acids?

a. Glutamic acid

In general, how does oxidative deamination differ from transamination?

Write the structure of the ⍺-keto acid produced by oxidative deamination of the following amino acids:

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a. Leucine

What other product is formed in oxidative deamination besides an ⍺-keto acid?

Draw the condensed structural formula for the α-keto acid produced from each of the following in transamination:

a.

Draw the condensed structural formulas for the products of the reaction of aspartate and α-ketoglutarate which is catalyzed by aspartate transaminase (AST).