What is the general function and structure of proteins?

Answer 1

Proteins build every part of our body. It is composed of monomers called ammino acid.

Answer 2

Proteins are frequently acknowledged as helpful, and are an important element of the load help application of all animals. people can change into heavily sick in the experience that they don't devour sufficient proper protein, the disease kwashiorkor being an severe kind of protein deficiency. Protein depending antibiotics and vaccines help to strive against disease, and we warmth and preserve our bodies with clothing and shoes that are frequently protein in nature (e.g. wool, silk and leather-depending). The deadly houses of protein pollution and venoms is a lot less widely loved. Botulinum toxin A, from Clostridium botulinum, is acknowledged because the superb poison regularly occurring. in accordance to toxicology study, a teaspoon of this toxin will be sufficient to kill a fifth of the international's inhabitants. The pollution produced with the help of tetanus and diphtheria microorganisms are just about as poisonous. a catalogue of truly poisonous proteins or peptides would also contain the venoms of many snakes, and ricin, the poisonous protein cutting-edge in castor beans. for stucture(s) of Protine(s) bypass to the internet website decrease than and scroll down

Answer 3

Proteins are generally regarded as beneficial, and are a necessary part of the diet of all animals. Humans can become seriously ill if they do not eat enough suitable protein, the disease kwashiorkor being an extreme form of protein deficiency. Protein based antibiotics and vaccines help to fight disease, and we warm and protect our bodies with clothing and shoes that are often protein in nature (e.g. wool, silk and leather).
The deadly properties of protein toxins and venoms is less widely appreciated. Botulinum toxin A, from Clostridium botulinum, is regarded as the most powerful poison known. Based on toxicology studies, a teaspoon of this toxin would be sufficient to kill a fifth of the world's population. The toxins produced by tetanus and diphtheria microorganisms are nearly as poisonous. A list of highly toxic proteins or peptides would also include the venoms of many snakes, and ricin, the toxic protein found in castor beans.

for stucture(s) of Protine(s) go to the website below and scroll down

Answer 4

Protein function, folding, and stability depend both on the fabric of the protein and on the surrounding environment. Conventionally, proteins have been studied in aqueous media. However, the influence of water on protein features is difficult to study in these systems. If water is introduced as a new variable in the experimental system, our understanding of proteins can be vastly enriched. To modify the aqueous media in contact with proteins, different approaches have been used. Proteins in low water systems such as reverse micelles or nearly anhydrous solvents have been extensively studied. In addition, mixtures of water with solutes (carbohydrates, glycerol, polyethyleneglycol (PEG), etc.) or organic miscible solvents (dimethylsulfoxide (DMSO), dimethylformamide (DMF), dioxane, alcohols, etc.) in different proportions have led to many interesting observations on protein behavior.

The optimization of certain protein features has become a major goal for biotechnological and industrial applications. For example, the study of the behavior of proteins in watercosolvent mixtures is useful to gain insight into how some of their properties may be improved. Some other potential advantages of enzyme catalysis in binary systems are the following: enhancement of catalysis, increased solubility of hydrophobic substrates, novel chemistry in synthetic applications, altered substrate specificity, and tolerance to extreme conditions (high temperatures, extreme pH, or salt). However, most of the attempts to improve protein features have been conducted on a trial-and-error basis; only in recent years have the mechanisms involved been revealed through the understanding of interplay between proteins and solvent.

In this article we present an overview of the studies about the behavior of protein function (ligand binding and catalytic properties) and structure (stability and folding) in watercosolvent binary systems. Prior to the description of the effects of these nonconventional systems over protein function and structure, a brief review of their general characteristics is presented, and finally possible applications in these watercosolvent systems are discussed.


Proteins, from the Greek proteios, meaning first, are a class of organic compounds which are present in and vital to every living cell. In the form of skin, hair, callus, cartilage, muscles, tendons and ligaments, proteins hold together, protect, and provide structure to the body of a multicelled organism. In the form of enzymes, hormones, antibodies, and globulins, they catalyze, regulate, and protect the body chemistry. In the form of hemoglobin, myoglobin and various lipoproteins, they effect the transport of oxygen and other substances within an organism.

Proteins are generally regarded as beneficial, and are a necessary part of the diet of all animals. Humans can become seriously ill if they do not eat enough suitable protein, the disease kwashiorkor being an extreme form of protein deficiency. Protein based antibiotics and vaccines help to fight disease, and we warm and protect our bodies with clothing and shoes that are often protein in nature (e.g. wool, silk and leather).
The deadly properties of protein toxins and venoms is less widely appreciated. Botulinum toxin A, from Clostridium botulinum, is regarded as the most powerful poison known. Based on toxicology studies, a teaspoon of this toxin would be sufficient to kill a fifth of the world's population. The toxins produced by tetanus and diphtheria microorganisms are nearly as poisonous. A list of highly toxic proteins or peptides would also include the venoms of many snakes, and ricin, the toxic protein found in castor beans.

Despite the variety of their physiological function and differences in physical properties--silk is a flexible fiber, horn a tough rigid solid, and the enzyme pepsin water soluble crystals--proteins are sufficiently similar in molecular structure to warrant treating them as a single chemical family. When compared with carbohydrates and lipids, the proteins are obviously different in fundamental composition. The lipids are largely hydrocarbon in nature, generally being 75 to 85% carbon. Carbohydrates are roughly 50% oxygen, and like the lipids, usually have less than 5% nitrogen (often none at all). Proteins and peptides, on the other hand, are composed of 15 to 25% nitrogen and about an equal amount of oxygen. The distinction between proteins and peptides is their size. Peptides are in a sense small proteins, having molecular weights less than 10,000.

I hope this helps you with your question.

Answer 5

general structure: amino acids
function: muscle growth and repair

Answer 6

Proteins are large organic compounds made of amino acids arranged in a linear chain and joined together between the carboxyl atom of one amino acid and the amine nitrogen of another. This bond is called a peptide bond. The sequence of amino acids in a protein is defined by a gene and encoded in the genetic code. Although this genetic code specifies 20 "standard" amino acids, the residues in a protein are often chemically altered in post-translational modification: either before the protein can function in the cell, or as part of control mechanisms. Proteins can also work together to achieve a particular function, and they often associate to form stable complexes.

Like other biological macromolecules such as polysaccharides and nucleic acids, proteins are essential parts of all living organisms and participate in every process within cells. Many proteins are enzymes that catalyze biochemical reactions, and are vital to metabolism. Other proteins have structural or mechanical functions, such as the proteins in the cytoskeleton, which forms a system of scaffolding that maintains cell shape. Proteins are also important in cell signaling, immune responses, cell adhesion, and the cell cycle. Protein is also a necessary component in our diet, since animals cannot synthesise all the amino acids and must obtain essential amino acids from food. Through the process of digestion, animals break down ingested protein into free amino acids that can be used for protein synthesis.

The name protein comes from the Greek πρώτα ("prota"), meaning "of primary importance" and were first described and named by Jöns Jakob Berzelius in 1838. However, their central role in living organisms was not fully appreciated until 1926, when James B. Sumner showed that the enzyme urease was a protein. The first protein structures to be solved included insulin and myoglobin; the first was by Sir Frederick Sanger who won a 1958 Nobel Prize for it, and the second by Max Perutz and Sir John Cowdery Kendrew in 1958.[1] Both proteins' three-dimensional structures were amongst the first determined by x-ray diffraction analysis; the myoglobin structure won the Nobel Prize in Chemistry for its discoverers.[2]

Proteins are linear polymers built from 20 different L-alpha-amino acids. All amino acids share common structural features including an alpha carbon to which an amino group, a carboxyl group, and a variable side chain are bonded. Only proline shows little difference in a fashion by containing an unusual ring to the N-end amine group, which forces the CO-NH amide sequence into a fixed conformation.[3] The side chains of the standard amino acids, detailed in the list of standard amino acids, have varying chemical properties that produce proteins' three-dimensional structure and are therefore critical to protein function. The amino acids in a polypeptide chain are linked by peptide bonds formed in a dehydration reaction. Once linked in the protein chain, an individual amino acid is called a residue and the linked series of carbon, nitrogen, and oxygen atoms are known as the main chain or protein backbone. The peptide bond has two resonance forms that contribute some double bond character and inhibit rotation around its axis, so that the alpha carbons are roughly coplanar. The other two dihedral angles in the peptide bond determine the local shape assumed by the protein backbone.

Due to the chemical structure of the individual amino acids, the protein chain has directionality. The end of the protein with a free carboxyl group is known as the C-terminus or carboxy terminus, while the end with a free amino group is known as the N-terminus or amino terminus.

There is some ambiguity between the usage of the words protein, polypeptide, and peptide. Protein is generally used to refer to the complete biological molecule in a stable conformation, while peptide is generally reserved for a short amino acid oligomers often lacking a stable 3-dimensional structure. However, the boundary between the two is ill-defined and usually lies near 20-30 residues.[4] Polypeptide can refer to any single linear chain of amino acids, usually regardless of length, but often implies an absence of a single defined conformation.Structure of proteins

Main article: Protein structure

Three possible representations of the three-dimensional structure of the protein triose phosphate isomerase. Left: all-atom representation colored by atom type. Middle: "cartoon" representation illustrating the backbone conformation, colored by secondary structure. Right: Solvent-accessible surface representation colored by residue type (acidic residues red, basic residues blue, polar residues green, nonpolar residues white).
Three possible representations of the three-dimensional structure of the protein triose phosphate isomerase. Left: all-atom representation colored by atom type. Middle: "cartoon" representation illustrating the backbone conformation, colored by secondary structure. Right: Solvent-accessible surface representation colored by residue type (acidic residues red, basic residues blue, polar residues green, nonpolar residues white).

Most proteins fold into unique 3-dimensional structures. The shape into which a protein naturally folds is known as its native state. Although many proteins can fold unassisted simply through the structural propensities of their component amino acids, others require the aid of molecular chaperones to efficiently fold to their native states. Biochemists often refer to four distinct aspects of a protein's structure:

* Primary structure: the amino acid sequence
* Secondary structure: regularly repeating local structures stabilized by hydrogen bonds. The most common examples are the alpha helix and beta sheet.[7] Because secondary structures are local, many regions of different secondary structure can be present in the same protein molecule.
* Tertiary structure: the overall shape of a single protein molecule; the spatial relationship of the secondary structures to one another. Tertiary structure is generally stabilized by nonlocal interactions, most commonly the formation of a hydrophobic core, but also through salt bridges, hydrogen bonds, disulfide bonds, and even post-translational modifications. The term "tertiary structure" is often used as synonymous with the term fold.
* Quaternary structure: the shape or structure that results from the interaction of more than one protein molecule, usually called protein subunits in this context, which function as part of the larger assembly or protein complex.

In addition to these levels of structure, proteins may shift between several related structures in performing their biological function. In the context of these functional rearrangements, these tertiary or quaternary structures are usually referred to as "conformations," and transitions between them are called conformational changes. Such changes are often induced by the binding of a substrate molecule to an enzyme's active site, or the physical region of the protein that participates in chemical catalysis.