It is a biochemical compound that consists both proteins and lipids. It is bonded by water. Many toxins, enzymes, transporters and adhesins are lipoproteins. Other examples are High-density Lipoproteins and Low Density Lipoproteins. What are Lipoproteins?
Its main function is to transfer Lipids such as cholesterol via the Blood stream. It helps the body to sustain its Nerve Cells and other vital cells in our body. It also helps the lipids to transport energy to the muscles. What are the functions of Lipoproteins?
Lipoproteins are classified into two, very dense and less dense. Very dense lipoproteins contain more lipids than proteins. They are categorized by Electrophoresis and ultracentrifugation. How to classify Lipoproteins by Density?
Chylomicrons- Carry Triacyl Glycerol to the liver, skeletal muscles and adipose tissue. Very Low Density Lipoproteins(VDL)- Carry newly synthesized Triacyl Glycerol to the liver and from the liver to the adipose tissue. What are the classifications of Lipoprotein by density?
Intermediate Density Lipoproteins (IDL)- The buffer between VLDL and HDL and are not detectable in the blood. They exist in very small amounts. Low Density Lipoproteins (LDL)- It carries Cholesterol from the liver to the body. High Density Lipoproteins (HDL)- It collects cholesterol from the body tissues then transported to the Liver.
In the exogenous pathway, small intestines were prepared to absorb lipids from food. Then, they were assembled together with Apoliprotein B-48 then merged to Chylomicrons. From the epithelial cells, they were circulated to the lymph vessels. The Chylomicrons were later drained to the bloodstream. How does the Lipoproteins metabolize through the Exogenous Pathway?
In the bloodstream, HDL would donate Apoliprotein C-II and Apoliprotein E to the Chylomicrons that were circulating. The sole purpose of Apoliprotein C-II was to activate Lipoprotein Lipase, an enzyme on the endothelial cells. LPL triggers the Hydrolysis of triglycerides which then ultimately releases them from the Chylomicrons. The lipids could then be absorbed by the muscles and other tissues in the body.
VLDL particles, formed when Apolipoprotein B-100 merged with Triacyl Glycerol and Cholesterol, would be first released to the blood stream. Then it would be loaded with Apolipoprotein C-II and Apolipoprotein E from HDL particles to become mature. How about the Endogenous pathway?
Mature VLDL would then be hydrolized by LPL that was activated by the Apolipoprotein C-II. Then, the lipids would be released and as the result, the VLDL would be converted to Intermediate Density Lipoproteins. They would be circulated back to the liver for reabsorption.
a protein that is soluble in water and in half-saturated salt solutions, in contrast to globulin, which is soluble only in dilute salt solutions. Coagulated by heat. Precipitated by saturation with ammonium sulfate.
include ovalbumin from egg white,lactalbumin from milk, and serum albumin from blood serum.
make up about half of the protein in human serum, where their main functions are to maintain normal water balance between blood and tissues by osmotic mechanisms and to serve as transport proteins for less soluble substances that can bind to them, such as amino acids.
detection of albumins in the urine is an indication of some types of kidney dysfunction.
Maintain normal water balance between blood and tissues by osmotic mechanisms
It binds water, cations (such as Ca2+, Na+ and K+), fatty acids, hormones, bilirubin and drugs
Regulate the colloidal osmotic pressure of blood
Prevention of red blood cell from sticking together
Albumin : Serum Albumin Most abundant blood plasma protein and is produced in the liver and forms a large proportion of all plasma protein It is a transport protein with one polypeptide chain, stabilized by 17-18 disulfide bridges contributed by 35 to 37 half cystine residues. It has one free sulfhydryl group. It possess a high content of basic & acidic amino acids. Important in regulating blood volume
Low albumin (Hypoalbuminemia) – may be caused by liver disease, nephrotic syndrome, burns, malnutrition
High albumin (Hyperalbuminemia) – always caused by dehydration
Normal range of human serum albumin in adults (>3 y. o.) is 3.5 to 5 g/dL.
For children less than 3 yrs. of age, the normal range is 2.9 to 5.5 g/dL.
is one of the three types of serum proteins, the others being albumin and fibrinogen. Some globulins are produced in the liver, while others are made by the immune system. The term globulin encompasses a heterogeneous group of proteins with typical high molecular weight, and both solubility and electrophoretic migration rates lower than for albumin. The normal concentration in blood is 2 to 3.5 g/dl.
can also be measured quantitively and qualitatively with electrophoresis.
Protein electrophoresis is used to categorize globulins into the following four categories:
Gamma globulins (one group of gamma globulins are immunoglobulins, that function as antibodies)
GLOBULIN: CATEGORIES Alpha Globulins are a group of globular proteins in plasma, which are highly mobile in alkaline or electrically charged solutions. They inhibit certain blood protease and inhibitor activity.
GLOBULIN: CATEGORIES Beta globulins are a group of globular proteins in plasma that are more mobile in alkaline or electrically charged solutions than gamma globulins, but less mobile than alpha globulins. Examples of beta globulins include:
GLOBULIN: CATEGORIES Gamma globulins are a class of globulins, identified by their position after serum protein electrophoresis. The most significant gamma globulins are immunoglobulins ("Igs"), more commonly known as antibodies, although some Igs are not gamma globulins, and some gamma globulins are not Igs.
Gamma globulin injections are usually given in an attempt to temporarily boost a patient's immunity against disease. Injections are most commonly used on patients who have been exposed to hepatitis A or measles, or to make a kidney donor and recipient compatible regardless of blood type of tissue match.
Gamma globulin infusions are also used to treat immunological diseases, such as idiopathic thrombocytopenia purpura (ITP), a disease in which the platelets are being attacked by antibodies, leading to seriously low platelet counts. Gamma globulin apparently causes the spleen to ignore the antibody-tagged platelets, thus allowing them to survive and function.
Pseudoglobulinsare a fraction of globulins that are soluble in ammonium sulfate solution more so than the euglobulin fraction. Pseudoglobulins are soluble in pure water, whereas euglobulins are insoluble under the same circumstances.
Collagen is one of the most plentiful proteins present in the bodies of mammals, including humans. Collagen is natural & fibrous protein which provides structural support to our bodies.
Collagen works hand-in-hand with elastin in supporting the body’s tissues. Basically, it gives body tissues form and provides firmness and strength and works with keratin to provide the skin with strength, smoothness, elasticity and resilience.
Collagen is the principal protein of the skin, tendons, cartilage, bone and connective tissue.
-It is made of 3 polypeptide chains, with about 1000 amino acids each and are generally of two kinds designated as α and α2 in a ratio of 2:1 suggesting the formula (α)2α2 .
Collagen is an important component of the body's connective tissues, which perform a variety of functions in the body.
Collagen is important to your health because it is the principal protein of skin, connective tissues, tendons, bones, teeth and cartilage
Collagen supports the internal organs. In these areas, collagen molecules create extensive sheets of strong connective tissue.
Collagen supplies the matrix in which calcium salts that give bones their hardness are deposited.
TYPE I -This is the most abundant collagen of the human body. It is found in tendons, skin, artery walls, many connective tissues and the organic part of bones and teeth.
TYPE II - Makes up 50% of all cartilage protein. Vitreous humour of the eye.
TYPE III - Found in artery walls, skin, intestines and the uterus
TYPE IV - Also serves as part of the filtration system in capillaries and it is found in basal lamina and eye lens.
Produced in the cells deep in the basal layer of the skin. As these cells are pushed up to the surface they die and form the minute white skin-scales which cover our bodies. Most of the keratin that people interact with is actually dead; hair, skin, and nails are all formed from dead cells which the body sheds.
Key structural material making up the outer layer of human skin. It is also the key structural component of hair and nails.
Found in reptiles, birds, amphibians, and mammals. The protein of claws and scales of reptiles, feathers and beaks of birds, horns, shells of turtles and hooves and hair of mammals
Extremely strong protein
Insoluble, due to extensive disulfide bonding.
Has a fairly rigid structure due to disulfide bridges between Individual molecules.
Unpleasant odor when burned due to high levels of sulfur in keratin.
Some are more flexible and elastic, such as hair, due to fewer interchain disulfide bridges. Some are more inflexible and hard, such as nails, hooves and claws.
Alpha-keratin - This is abundant in humans and mammals.
Ex: hair, wool, horns, nails, claws and hooves of mammals
Beta-keratin - is primarily in birds and reptiles. However, beta sheets are also found in α-keratins.
Ex: scales and claws of reptiles, shells of turtles and turquoise, and in the feathers, beaks, claws of birds and quills of porcupines.