Chapter 10, Problem 20DAP

(a)

Summary Introduction

To determine:

The ganglioside, which fits in the description given in the question.

Introduction:

Ganglioside is a biomolecule made of a glycosphingolipids. Gangliosides are found in the cell membrane and the main function of these molecules is to modulate the cell signal transduction processes. They consist of a sialic acid like n-acetylneuraminic acid (NANA) which makes the anionic head groups of the gangliosides.

(b)

Summary Introduction

To determine:

The report of Svennerholm, that “90% of the monosialogangliosides from a patient with Tay-Sachs had a molar ratio of 1:2:1:1” is consistent with the Box 10-1 figure.

Introduction:

Tay-Sachs is a central nervous system disease, which commonly affects the children of 4-5 years old. This disease is caused by a defective gene (HEX-A) on the chromosome 1. The defect in the HEX-A gene causes the body to not synthesize a protein called hexosaminidase. The deficiency of this protein causes the accumulation of the gangliosides in the nerve cells of the brain, that leading a brain failure.

(c)

Summary Introduction

To determine:

The conclusion, a person can obtain from the structure of the normal ganglioside, and determine the resulting structure is consistent with the structure in Box 10-1.

Introduction:

Gangliosides are the biomolecules composed of glycosphingolipids. They consist a sialic acid like n-acetylneuraminic acid (NANA) that forms the anionic head groups of the gangliosides. Gangliosides are found in the cell membrane and the main function of these molecules is to modulate the cell signal transduction processes. The hydrophilic unit of the ganglioside is the sialic acid, and hydrophobic unit is sphingosine.

(d)

Summary Introduction

To determine:

The conclusion, a person can obtain from the structure of the Tay-Sachs ganglioside, and determine the resulting structure is consistent with the structure in Box 10-1.

Introduction:

Tay-Sachs is a genetic disorder of central nervous system, in which the brain cells destroyed due to the deficiency of the protein hexosaminidase. In this disorder, a defect occurs in the gene HEX-A, which is responsible for the protein hexosaminidase. Whereas, Gangliosides are the biomolecules found in the cell membrane and composed of glycosphingolipids. The main function of these molecules is to modulate the cell signal transduction processes.

(e)

Summary Introduction

To determine: The sugar of GM1 that each of the permethylated sugars corresponds.

Introduction:

Monosialotetrahexosylganglioside (GM1) is the prototype of gangliosides that contain a sialic acid unit. GM1 plays an important role in neuronal plasticity and repair mechanisms. It is also responsible for the release of neutrophins in the Central Nervous System (CNS). GM1 also provides the binding site for the E. coli heat-labile enterotoxin and Cholera toxin.

(f)

Summary Introduction

To determine:

The missing pieces of information about the normal gangliosides structure based on all the data presented so far.

Introduction:

Gangliosides are found in the cell membrane and play an important role in modulating the cell signal transduction processes. Ganglioside are composed of glycosphingolipids. They consist of a sialic acid like n-acetylneuraminic acid (NANA) which makes the anionic head groups of the gangliosides.