Functions of glycolipid

Description of the functions of glycolipids.
Glycolipids are glycogen attached to lipid molecules

1. FUNCTIONS OF GLYCOLIPID PRESENTATION MADE BY HETAKUMARI PILUDARIA AND PRERNA RANI BSc (HONS) BIOTECHNOLOGY SEM I

2. INTRODUCTION Glycolipids are derivatives of ceramides and spingosine with carbohydrate directly attached to ceramide . HPILUDARIA 2

3. EXAMPLES Cerebroside The simplest glycolipid Ganglioside An example of complex glycolipid HPILUDARIA 3

4. Glycolipid plays important role in the following- Cell-cell interaction Structure of cell membrane Immune Responses Blood types Surface receptors Part of nervous tissue Part of Muscle tissue Cell Growth Diseases related to Glycolipid. CONTENTS HPILUDARIA 4

5. Role of Glycolipid in Cell- cell interaction Serves as recognition sites for cell-cell interaction. Sugar moiety of glycolipid binds to a specific complimentary carbohydrate. thus glycolipid acts as cell markers HPILUDARIA 5

6. Glycolipid in Cell Membrane Glycolipid in aqueous medium forms a bimolecular sheet instead of micelle. Two fatty acids chains of glycolipid are too bulky to fit into interior of micelle . And so it forms a bilayer similar to that of phospholipid. The resulting hydrophobic interactions have three significant biological consequences HPILUDARIA 6

7. The strong interaction between glycolipids and cholesterol is the driving force which segregates from the fluid phospholipid from the membrane The resulting hydrophobic interactions have three significant biological consequences It has tendency to be extensive Tend to close on themselves so that there are no edges with exposed hydrocarbon chains and so form compartments Bilayers are self sealing because a hole in a bilayer is energetically unfavorable. HPILUDARIA 7

8. Role of Glycolipid in Immune Response Immune responses are generated when the carbohydrate attached to the glycolipid binds to a specific site of leukocytes and endothelial cells. Sugar moeity has special compliment binding sites HPILUDARIA 8

9. Glycolipids are responsible for different blood groups G lycolipids are membrane components composed of lipids that are covalently bonded to monosaccharides or polysaccharides. One type of glycolipid found in human red blood cells is involved in the ABO blood type antigens. HPILUDARIA 9

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14. GLYCOLIPID AS CELL SURFACE RECEPTORS The carbohydrate part of the glycolipid have particular binding sites Receptors will bind to the sugar part of the glycolipid HPILUDARIA 14

15. PART OF NERVOUS TISSUE Glycolipids are widely distributed in every tissue of the body, particularly in the nervous tissue, such as brain. They occur particularly in the outer leaflet of the plasma membrane where they contribute to cell surface carbohydrates . Gangliosides are present in nervous tissue in high concentration and are associated with calcium ions. HPILUDARIA 15

16. Part of muscle tissue Cerebrosides are present in large amount in animal muscle tissue. HPILUDARIA 16

17. Cell growth Glycosphingolipids have been associated with growth factor receptors Glycolipid interact with growth factor receptors HPILUDARIA 17

18. Diseases related to glycolipids Certain diseases are caused due to the abnormal quantities of glycolipids in animal tissues, especially in central nervous system. HPILUDARIA 18

19. Ganglioside storage disease are inherited disorders of lysosomal hydrolase enzymes Results in accumulation of gangliosides and glycolipid substrate accumlation within lysosomes of neurons and glia throughout the nervous system. HPILUDARIA 19

20. LEUKODYSTROPHY Caused by deficency b- galactocerebrosidease Resut in accumulation of galactocerebroside within the nervous system. HPILUDARIA 20

21. References http:// academic.brooklyn.cuny.edu/biology/bio4fv/page/glycol.htm Reginald H. Garret, Charles M. Grisham. Biochemistry Donald J. Voet , Judith G. Voet , Charlotte W. Partt . Principles of Biochemistry, International Edition. Thomas M. Devlin. Textboo of biochemistry with clinical corelation . 6 th edition Jeremy M. Berg, John L. tymoczk , Lubert stiyer . Biochemistry, 5 th Edition Robert K. Murray, Daryl K. Granner , Peter A. Mmayes , Victor W. Rodwell . Harper’s Illustrated Biocheisty . 26 th edition. HPILUDARIA 21

22. THANK YOU HPILUDARIA 22