Salt Bridges of protein

A salt bridge is defined as a hydrogen bonded pair of charges of opposite sign. Obviously, the formation of a salt bridge depends on the protonation state of the partners and hence on pH.

Salt bridges are interactions of amino acids with opposite charge where at least two heavy atoms lie within a hydrogen bonding distance. Often found in solvent exposed parts of proteins, they are susceptible to external interactions, primarily with water.

In a salt bridge, a proton migrates from a carboxylic acid group to a primary amine or to the guanidine group in Arg. Typical salt bridges involve Lys or Arg as the bases and Asp or Glu as the acids. Of all the non-covalent interactions, salt bridges are among the strongest.

Salt bridges contribute to protein structure and to the specificity of interaction of proteins with other biomolecules, but in doing so they need not necessarily increase a protein's free energy of unfolding.

The net electrostatic free energy of a salt bridge can be partitioned into three components: charge–charge interactions, interactions of charges with permanent dipoles, and desolvation of charges.

Salt Bridges of protein

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The properties of protein

It is can be defined as ‘any of numerous organic molecules constituting a large portion of the mass of every life form, composed of 20 or more amino acid linked in one or more long chains, the final shape and other properties of each protein being determined by the side chains of the amino acids and their chemical attachments.

Knowing the function and structure of proteins is crucial for the development of better drugs, higher yields crops, and even synthetic biofuels.

Some proteins are involved in complex biochemical activities. Others contribute to the structure of cells. 

Proteins are composed of carbon, hydrogen and nitrogen, and sometimes sulfur and phosphorus. All proteins contain nitrogen at a level of about 16%. The analysis of proteins is determined indirectly by analyzing for protein nitrogen, then multiplying the result by 6.25 to determine the actual amount of protein analyzed.

It is a biological macromolecule composed of a series of smaller, building block molecules called amino acids, linked together in a linear chain, like beads on a string. Different proteins contain different amino acids.

Proteins are joined covalently and non-covalently with other biomolecules including lipids, carbohydrates, nucleic acids, phosphate groups, flavins, heme groups and metal ions. Components such as hemes or metal ions are often called prosthetic groups.

Complexes formed between lipids and proteins are lipoproteins, those with carbohydrates are called glycoproteins, whilst complexes with metal ions lead to metalloproteins.

The hydrophobic effect is the driving forces in the formation of active protein structure. The stability of protein molecules is maintained principally by hydrogen bonding and hydrophobic interactions, which play a crucial role in the formation of the tertiary structure of soluble proteins and oligomeric structure.

This nutrient has a limited life span and constantly undergoes change. The rate of protein turnover varies in different tissues.
The properties of protein

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What is tocotrienols?

Tocopherols and tocotrienols which are collectively known as tocochromanols, belongs to the group of vitamin E compounds.

Tocotrienols occupy a special place due to their unique chemical structure and properties. They are generally located in seeds and fruits; however, there is a high variation in the relative abundance for each tocotrienols homologue.

Tocotrienols are a group of four amphipathic molecules (alpha, beta, gamma, delta) that differ in the number and position of the methyl groups in the polar head.

Delta-tocotrienols tends to be the predominant form found in seeds, followed by alpha and gamma forms, whereas gamma-tocotrienols is the predominant form in fruits.

The gamma-tocotrienols is the most prevalent form in nature and it also appears to be the form with strongest potential for dietary health benefits.

Most tocotrienols from market are derived form rice bran oil and palm oil. Presently marketed forms of tocotrienols contain mixed tocotrienols in their unesterified forms.

The major sources of tocotrienols are plant, oils, and the richest sources are palm oil, rice bran oil, palm kernel oil and coconut oil.

Tocotrienols are not found in the green parts of plants but, rather in the bran and germ fraction of certain seeds and cereals. All of the natural tocotrienols are fat-soluble, water insoluble oils.
What is tocotrienols?

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The Protein Structure

The Protein Structure
The basic structure common to all proteins is the peptide linkage which is formed by condensation the carboxyl group of one of amino acid with the amino group of another.

In this way chains are created, which contains only 3 amino acids, to complex polymers of 1000 or more.

The sequence in which amino acids are arranged in the peptide chain is known as the primary structure of the molecule.

The proper sequence of amino acids tends to be a critical factor in protein function.

In some heritable disease, such as sickle cell anemia, the defect is due to the genetic substitution of only one amino acid in the hemoglobin molecule.

Differences in sequence of three amino acids in insulin from different species, however, do not affect the activity of the hormone apparently, because this three amino acid sequence is not an active site of the molecule.

Biological activity of a protein, however, depends not only on the sequence of the amino acids but also on the spatial arrangement of the long peptide chain.

Although the peptide bond is the primary and also the strongest linkage ion the protein polymer, other peptides of bonding occur.

These additional linkages or secondary bonds are partly responsible or the arrangement of the molecule.
The Protein Structure

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