Protein function for Human Life

Protein function - In human life, protein is very important in supporting the existence of the entire human body cells. This is because the proteins have molecules containing oxygen, carbon, nitrogen, hydrogen, and sulfur. Some proteins also contain phosphorus. For adults, should consume at least 1 gram of protein per kg of body weight.

The word protein comes from the Greek word protos meaning "most important". Was first discovered by Jons Jakob Berzelius in 1838. Proteins are complex organic compounds of high molecular weight. The function of proteins is very important in the structure and function of living cells, because it carries the genetic code in the form of DNA and RNA.

Protein is formed from amino acids. Amino acids are divided into:

1. Essential Amino Acids

Amino acids that can not be formed by the body. There are 8 in number, namely, isoleucine, leucine, lysine, methionine, valine, tryptophan, and fenilanin tronin.

2. Non-Essential Amino Acids

Amino acid can be synthesized by the body such as alanine, asparagine, glycine, glutamine and proline.

Protein Function

It has been said that the protein is essential for the cells of living things including humans therein. More The obvious function of the protein for the body are:

•     As a source of energy.
•     As the material for the enzyme mengkatalisi biochemical reactions.
•     Serves to transfer substances or certain elements, such as hemoglobin to bind O2. This function is performed by the transport protein.
•     As the contraction of certain tissues, such as muscle myosin for contraction is a function of the contractile potein.
•     As the immune response and the immune system of foreign substances.
•     As the regulatory processes in the body, which is a hormone made by the protein.
•     As a constituent structure of cells, tissues and body of a living organism. It is a function of the structural proteins.
•     As a regulator of the balance of acid levels in the cell.

The function of protein for humans play a role in the growth of the man himself. For that men should consume resources that contain protein. The protein sources are twofold, namely animal protein and vegetable protein.

Animal protein of animal origin such as meat, fish, eggs, milk. Meanwhile, vegetable protein derived from plants, such as nuts, seeds and plant potatoes.

Classification of Proteins

Protein was mixed. Based on the shape, the protein is divided into

1. Protein fibers (fibrous)

This protein spiral of several peptide chains. The characteristics of these proteins is the low solubility, has a high strength to resist digestive enzymes. The types of proteins, namely:

•     Collagen (the main protein of connective tissues
•     Elasti (a protein found in tendons, muscles, blood vessels (arteries) and other elastic tissues)
•     Keratini (protein for hair and nails)
•     Myosin (the main protein for muscle fibers)

2. Protein Gobuler

These proteins are found in the tissues of the body fluids. The shape is round like a ball. This protein is readily soluble in saline solution, easy to change due to temperature, salt concentration. This protein is found in muscle, serum, and egg yolks. Based on the solubility, globular proteins are divided into:

•     Albumin. This protein is soluble in water terkoagulasi by heat. For example, egg albumin, serum albumin.
•     Globulin. This protein is water insoluble, terkoagulasi by heat, and can be dissolved in a solution of salt and sediment. For example, ixiosinogen in muscle.
•     Plolamin / gliadin. Soluble in 70-80% alcohol and insoluble in water and absolute alcohol. For example, prolaamin in wheat.
•     Glutelin. That is not soluble in neutral solvents namu soluble in acid or alkaline liquid. For example, Histo in Hb.
•     Histon: protein is soluble in water and insoluble in aqueous ammonia. For example, Hisron in Hb.
•     Protamin. This protein is soluble in water and does not terkoagulasi by heat. It is the simplest protein compared to other proteins. For example, the bond salmin salmon.

3. Protein Conjuction

That is, the protein bound to the material non-amino acids.

While based on biological functions, proteins can be divided into:

1. Enzyme

a protein that is the most important and largest. There are a thousand kinds of enzymes are known. The function of the enzyme protein is useful as a catalyst. Enzyme molecules are generally spherical and different types of enzymes in the body of a different life.

Examples of such enzyme ribonuclease, an enzyme which catalyzes hidroliga RNA, cytochrome that functions in the process of moving electrons, trypsin catalytic peptide bond breaker.

2. Protein Builders

This protein functions as forming element. For example pembukus viral protein (chromosome sheath), glycoprotein (supporting structure of the cell wall), membrane structure, sklerotin (contained in the cocoons of silkworms) and others.

3. Contractile Protein

Proteins that function in the movement. For example, myosin.

4. Protein Carrier

Proteins that can bind specific molecules through the bloodstream. For example, the iron-containing hemoglobin, the oxygen transport function in the vertebrate blood.

5. Protein Toxins

Proteins are toxic to animals of high class. For example botulimum clostridium toxins, which can cause food poisoning or even poisonous snakes.

6. Protective Protein

Protective protein function helps to protect the body from foreign substances. For example, antibody.

7. Protein Reserves

These proteins function in metabolic processes. Ovalbumim example, the protein is in the egg whites, casein protein in corn grain.

The function of protein - Protein Structure

Protein has four hierarchical structure, namely:

1. Primary Structure of Proteins

The primary structure of the protein, which is the sequence of amino acids making up the protein are linked by peptide bonds. Sequence of amino acids determines the protein's function. And it can also alter its function and can trigger mutations genetik.Struktur can be determined by the method:

•     Protein hydrolysis with strong acids, and amino acids is determined by the amino acid analyzer instrument.
•     Sequence analysis using Edman degradation of the end-N.
•     Combination with trypsin digestion and mass spectrometry.
•     Molecular mass determined by mass spektromentri.

2. Protein Secondary Structure

Secondary structure of proteins, namely the structure of the various amino acid sequences which are stabilized by hydrogen bonds. This structure can be determined by circular dichroism spectroscopy (CD) and Fourier Transform Infra Red (FTIR). The forms of the protein secondary structure is:

•     Alpha helix. Spiral chains of amino acids that form a spiral.
•     Beta sheet, or "beta plate". These sheets are composed of several chains of amino acids are bonded through hydrogen bonds or bond thiol (SH).
•     Beta-turn or "curve-beta".
•     Gamma-turn or "gamma curve".

3. Tertiary Structure of Proteins

Tertiary structure of proteins, which combines a wide range of secondary structures. This structure is generally in the form of lumps.

4. Quaternary structure of proteins

Quaternary structure of proteins, the structures resulting from the interaction of multiple protein molecules without forming a covalent bond is a stable oligomer. An example of this is the quaternary structure of the enzyme RuBisCO and insulin.

In addition to the four protein structural hierarchy above, actually there is another structure of the protein domain structure. In general, a simple protein has only one domain. And these structures are composed of amino acids 40-350.

Protein Function - Due to Lack of Protein

The human body really needs protein. In addition to supporting the presence of protein function of every cell in the body, it also serves to the immune system (immune). Protein deficiency can be fatal to humans. Among the effects are:

•     Hair loss. Hair itself comprises about 97-100% Keratin Protein.
•     Onset of the disease kwashiorkor. Usually disproportionately affects children or also called starvation.
•     Death. Protein deficiency is constantly can result in death.

To get protein, keep in mind the daily diet, and of course find out information about the foods that contain lots of protein and its function. Thus, we can know the true function of the protein for the body.