This document summarizes a seminar presentation on the structure and function of lipoproteins. It first provides background on lipoproteins, noting that they are lipid molecules conjugated with protein that transport lipids like cholesterol and triglycerides through the bloodstream. It then details the classification of major lipoproteins like chylomicrons, VLDL, LDL, and HDL; their roles in lipid transport; and associated diseases like atherosclerosis. The document concludes by emphasizing the importance of lipoproteins for overall health and lipid metabolism.

1. SUBMITTED BY:-
VINAY M
I MSc I SEM
PG Department of Biotechnology
Sahyadri Science College
Shivamogga-577203
UNDER THE GUIDENCE OF
Dr. PRADEEPA K
Assistant Professor
PG Department of Biotechnology
Sahyadri Science College
Shivamogga-577203
KUVEMPU UNIVERSITY
SAHYADRI SCIENCE COLLEGE, SHIVAMOGGA-577 203
PG DEPARTMENT OF BIOTECHNOLOGY
SEMINAR TOPIC ON – STRUCTUREANDFUNCTIONSOFLIPOPROTEIN

2.  INTRODUCTION
 HISTORY
 STRUCTURE OF LIPOPROTEINS
 MECHANISM OF LIPOPROTEINS
 ROLE OF LIPOPROTEINS
 BIOLOGICAL SIGNIFICANCE
 TYPES (CLASSIFICATION)
 ASSOCIATED DISEASES
 CONCLUSION
 REFERENCE

3.  Lipoproteins is one of the component of compound lipids.
 These are the lipid molecules conjugated with the protein molecules.
 They contain triglycerol, phospholipids, cholesterol & cholesteryl esters, free fatty
acids and also proteins in combination.
 They carry cholesterol through our blood stream to the cells.
 Lipoprotein are an important component of the cell membrane and their special
structure is responsible for the active permeability properties of the cell membrane.
 They also play an important role in electron transport system of mitochondria.
 A lipoprotein is a biochemical assembly whose primary function is to transport
hydrophobic lipid molecules in water, as in blood plasma or other extra cellular fluids.

4. Lipoprotein (a), was discovered in the 1960s by the
Norwegian physician Kare Ingmar Berg.
Kare Berg
(1932 – 2009)

5.  Lipoproteins are complex particles that have a central
hydrophobic core of non-polar lipids, primarily
cholesteryl esters and triglycerides.
 Lipid portion – Cholesterol and triglycerides.
 This hydrophobic core is surrounded by a hydrophilic
membrane consisting of phospholipids, free
cholesterol, and apolipoprotein.
 Protein portion - Apolipoproteins

6. The transport of triglycerol and cholesterol by lipoproteins.

7.  Transport of triglycerides from intestine & liver to peripheral tissues (dietary &
stored fatty acids)
 Transport of cholesterol & phospholipids to peripheral tissues, glands, and liver
(reverse)
 Transport of liposoluble vitamins
 Transport of antioxidant enzymes
 Neutralization of endotoxins
 Effect of oxidised lipids on immune defenses and inflammation

8.  Transportation of Lipids : Lipoproteins transport lipids, including cholesterol and triglycerides,
throughout the body.
 Cellular Function : They deliver lipids to tissues for energy production, hormone synthesis, and cell
membrane maintenance.
 Cholesterol Metabolism : Lipoproteins are involved in cholesterol metabolism, essential for processes
like bile acid synthesis and steroid hormone production.
 Prevention of Diseases : Balanced lipoprotein levels are crucial for preventing cardiovascular diseases
such as atherosclerosis and coronary artery disease.
 Overall Health Maintenance : Understanding lipoproteins' role is vital for maintaining optimal health
and preventing diseases related to lipid metabolism.

9.  Chylomicrons
 Very low density lipoproteins
 Intermediate density lipoproteins
 Low density lipoproteins
 High density lipoproteins

10.  Chylomicrons, the largest of the lipoproteins[75-
600nm], are synthesized in the intestine.
 They transport ingested triacylglycerols to other
tissues mainly skeletal muscle and adipose tissue,
and transport ingested cholesterol to the liver.
 Chylomicron is also known as ultra low density
lipoprotein(ULDL).
 They are responsible for the transport of all dietary
lipids into the circulation.

11.  Very Low-Density Lipoprotein (VLDL) is a type of
lipoprotein primarily synthesized by the liver to
transport triglycerides, cholesterol, and other lipids
through the bloodstream.
 Predominantly consists of triglycerides (50-60%),
cholesterol (10-15%), phospholipids (20-25%), and
proteins (5-10%), primarily apolipoprotein B-100.
 Transports lipids from the liver to peripheral
tissues, providing energy through triglyceride
metabolism.

12.  IDL is a type of lipoprotein that is intermediate
in density between VLDL (Very Low-Density
Lipoprotein) and LDL (Low-Density
Lipoprotein).
 It is formed during the metabolism of VLDL in
the bloodstream.
 Contains a mixture of triglycerides, cholesterol,
phospholipids, and proteins with a composition
that is intermediate between VLDL and LDL.
 Apolipoprotein B-100 is the primary protein
component similar to VLDL and LDL.
 IDL plays a transitional role in lipid metabolism,
serving as an intermediate between VLDL,
which transports lipids from the liver to
peripheral tissues.

13.  LDL is a type of lipoprotein primarily composed of
cholesterol, with a smaller proportion of triglycerides,
phospholipids, and proteins.
 It is often referred to as "bad cholesterol" due to its
role in contributing to atherosclerosis.
 Contains primarily cholesterol (50% of its weight) and
smaller amounts of triglycerides, phospholipids, and
proteins.
 Transports cholesterol from the liver to peripheral
tissues, including cells throughout the body.
 Provides cholesterol for cell membrane formation,
hormone synthesis, and bile acid production.

14.  HDL is a type of lipoprotein primarily
composed of proteins with a smaller
proportion of cholesterol, phospholipids, and
triglycerides.
 It is often referred to as "good cholesterol"
due to its role in removing cholesterol from
the bloodstream.
 Contains high levels of proteins (about
50%of its weight),particularly
apolipoproteins such as apoA-I and apoA-II.
 Contains lower levels of cholesterol,
phospholipids,and triglycerides compared to
LDL and VLDL.

15.  Atherosclerosis
 Coronary Artery Disease
 Peripheral Artery Disease
 Ischemic Stroke
 Hyper Tension
 Family Hypercholesterolemia

16. Blood is watery & cholesterol is fatty, to transport cholesterol in the blood stream, it needs
to carry in small packages called lipoproteins.

17.  Gofman JW, Jones HB, Lindgren FT, Lyon TP, Elliott HA, Strisower B (August
1950). "Blood lipids and human atherosclerosis".
 "Microbial Proteolipids and Lipopeptides - glycopeptidolipids, surfactin, iturnins,
polymyxins, daptomycin". The LipidWeb. Retrieved 21 July 2019.
 Satyanarayana, U. (2002). Biochemistry (2nd ed.). Kolkata, India: Books and
Allied.