Chapter 25, Problem 25.105EP

(a)

Interpretation Introduction

Interpretation:

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid intermediate butyrate has to be determined.

Concept introduction:

Lipogenesis is the process employed for the synthesis of fatty acid. The starting precursor for the synthesis is acetyl CoA. The enzyme employed for the process is fatty acid synthase. It is a multienzyme complex that ties the reaction responsible for the synthesis of fatty acid. This process is the reverse of the degradation of fatty acid.

The Citric acid cycle is a series of biochemical reactions that use acetyl CoA (produced by oxidation of pyruvate) to produce carbon dioxide, NADH and FADH₂ in a series of redox reactions.

Answer to Problem 25.105EP

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid butyrate intermediate is succinate.

Explanation of Solution

Intermediates involved in the lipogenesis are derivative of C₄ molecule butyric acid. Butyric acid is a monocarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the lipogenesis is a C₄ derivative of monocarboxylic acid. The structure of butyric acid is,

Succinic acid is a dicarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the citric acid cycle is a ${\text{C}}_{\text{4}}$ derivative of dicarboxylic acid. The structure of succinic acid is,

The structure of butyrate is,

The structure of succinate is,

Butyrate and succinate are saturated acids with four carbon atoms in each molecule. Butyrate is a monoacid that is formed as an intermediate in lipogenesis while succinate is a diacid that is formed as an intermediate in the citric acid cycle. Therefore, the citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid butyrate intermediate is succinate.

(b)

Interpretation Introduction

Interpretation:

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid intermediate acetoacetate has to be determined.

Concept introduction:

Lipogenesis is the process employed for the synthesis of fatty acid. The starting precursor for the synthesis is acetyl CoA. The enzyme employed for the process is fatty acid synthase. It is a multienzyme complex that ties the reaction responsible for the synthesis of fatty acid. This process is the reverse of the degradation of fatty acid.

The Citric acid cycle is a series of biochemical reactions that use acetyl CoA (produced by oxidation of pyruvate) to produce carbon dioxide, NADH and FADH₂ in a series of redox reactions.

Intermediates involved in the lipogenesis are derivatives of C₄ molecule butyric acid. Butyric acid is a monocarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the lipogenesis is a C₄ derivative of monocarboxylic acid. The structure of butyric acid is,

Succinic acid is a dicarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the citric acid cycle is a C₄ derivative of dicarboxylic acid. The structure of succinic acid is,

Answer to Problem 25.105EP

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid acetoacetate intermediate is oxaloacetate.

Explanation of Solution

Acetoacetate is the intermediate in the lipogenesis. The structure of acetoacetate is,

Oxaloacetate is the intermediate in the citric acid cycle. The structure of oxaloacetate is,

Acetoacetate and oxaloacetate are the keto derivatives of saturated acid with four carbon atoms in each molecule. Acetoacetate is a keto derivative of monocarboxylic acid while oxaloacetate is a keto derivative of dicarboxylic acid. Therefore, the citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid acetoacetate intermediate is oxaloacetate.

(c)

Interpretation Introduction

Interpretation:

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid intermediate β-hydroxybutyrate has to be determined.

Concept introduction:

Lipogenesis is the process employed for the synthesis of fatty acid. The starting precursor for the synthesis is acetyl CoA. The enzyme employed for the process is fatty acid synthase. It is a multienzyme complex that ties the reaction responsible for the synthesis of fatty acid. This process is the reverse of the degradation of fatty acid.

The Citric acid cycle is a series of biochemical reactions that use acetyl CoA (produced by oxidation of pyruvate) to produce carbon dioxide, NADH and FADH₂ in a series of redox reactions.

Intermediates involved in the lipogenesis are derivatives of C₄ molecule butyric acid. Butyric acid is a monocarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the lipogenesis is a C₄ derivative of monocarboxylic acid. The structure of butyric acid is,

Succinic acid is a dicarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the citric acid cycle is a C₄ derivative of dicarboxylic acid. The structure of succinic acid is,

Answer to Problem 25.105EP

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid β-hydroxybutyrate intermediate is malate.

Explanation of Solution

β-Hydroxybutyrate is the intermediate in the lipogenesis. The structure of β-hydroxybutyrate is,

Malate is the intermediate in the citric acid cycle. The structure of Malate is,

β-Hydroxybutyrate and malate are the hydroxy derivatives of saturated acid with four carbon atoms in each molecule. β-Hydroxybutyrate is a hydroxy derivative of monocarboxylic acid while malate is a hydroxy derivative of dicarboxylic acid. Therefore, the citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid β-hydroxybutyrate intermediate is malate.

(d)

Interpretation Introduction

Interpretation:

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid intermediate crotonate has to be determined.

Concept introduction:

Lipogenesis is the process employed for the synthesis of fatty acid. The starting precursor for the synthesis is acetyl CoA. The enzyme employed for the process is fatty acid synthase. It is a multienzyme complex that ties the reaction responsible for the synthesis of fatty acid. This process is the reverse of the degradation of fatty acid.

The Citric acid cycle is a series of biochemical reactions that use acetyl CoA (produced by oxidation of pyruvate) to produce carbon dioxide, NADH and FADH₂ in a series of redox reactions.

Intermediates involved in the lipogenesis are derivatives of C₄ molecule butyric acid. Butyric acid is a monocarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the lipogenesis is a C₄ derivative of monocarboxylic acid. The structure of butyric acid is,

Succinic acid is a dicarboxylic acid and has 4 carbon atoms. Thus, each intermediate of the citric acid cycle is a C₄ derivative of dicarboxylic acid. The structure of succinic acid is,

Answer to Problem 25.105EP

The citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid crotonate intermediate is fumarate.

Explanation of Solution

Crotonate is the intermediate in the lipogenesis. The structure of crotonate is,

Fumarate is the intermediate in the citric acid cycle. The structure of fumarate is,

Crotonate and fumarate are the unsaturated derivatives of a carboxylic acid with four carbon atoms in each molecule. Crotonate is an unsaturated derivative of monocarboxylic acid while fumarate is an unsaturated derivative of dicarboxylic acid. Therefore, the citric acid cycle diacid intermediate counterpart for lipogenesis C₄-ACP monoacid crotonate intermediate is fumarate.