Chapter 14, Problem 31DAP

(a)

Summary Introduction

To determine: The reason that why it is simpler strategy than the reverse engineering E. coli to be more ethanol tolerant.

Introduction:

“Anaerobic harvest” of food energy is known as fermentation. This condition occurs in the absence of oxygen. In humans, the process of fermentation relies on the first stage that is glycolysis of the cellular respiration. This process allows production of two molecules of ATP from one glucose molecule which is less in comparison to the ATP molecules produced by cellular respiration. Whereas in microorganisms, this process is the primary means of ATP production by break down of organic nutrients in the absence of oxygen.

(b)

Summary Introduction

To determine: The chemical transformation catalyzed by each of three ara enzymes.

Introduction:

The ara genes produce enzymes that convert L-arabinose into L-xylulose-5-phosphate. This is a multistep reaction which includes three different enzymes encoded by different ara genes.

(c)

Summary Introduction

To determine: The name of the sugar which is converted from arabinose by three ara enzymes.

Introduction:

The ara genes produce three different enzymes encoded by different ara genes that is used to convert L-arabinose .

(d)

Summary Introduction

To describe: The overall pathway for the fermentation of six molecules of arabinose to ethanol.

Introduction:

“Anaerobic harvest” of food energy is known as fermentation. This is a metabolic process carried out mainly by yeast and some bacteria. They convert sugar into carbon dioxide and ethanol.

(e1)

Summary Introduction

To determine: The stoichiometry of the fermentation of six molecules of arabinose to ethanol and CO₂.

Introduction:

“Anaerobic harvest” of food energy is known as fermentation. This is a metabolic process carried out mainly by yeast and some bacteria. They convert sugar into carbon dioxide and ethanol.

(e2)

Summary Introduction

To determine: The number of ATP molecules that would be generated in this reaction.

Introduction:

“Anaerobic harvest” of food energy is known as fermentation. This is a metabolic process carried out mainly by yeast and some bacteria. They convert sugar into carbon dioxide and ethanol.

(f)

Summary Introduction

To explain: The reason that production of 1 ATP per molecule of arabinose is less beneficial for bacterium but better for production of ethanol.

Introduction:

“Anaerobic harvest” of food energy is known as fermentation. This is a metabolic process carried out mainly by yeast and some bacteria. They convert sugar into carbon dioxide and ethanol.

(g)

Summary Introduction

To determine: The additional enzymes that would allow Z. mobilis to use xylose as well as arabinose to produce ethanol.

Introduction:

“Anaerobic harvest” of food energy is known as fermentation. This is a metabolic process carried out mainly by yeast and some bacteria. They convert sugar into carbon dioxide and ethanol.