what is chemical nature of enzymes?

Answer 1

Chemical nature

All enzymes are proteins. Their molecular weights range from about 10,000 to more than 1,000,000. Like other proteins, enzymes consist of chains of amino acids linked together by peptide bonds. An enzyme molecule may contain one or more of these polypeptide chains. The sequence of amino acids within the polypeptide chains is characteristic for each enzyme and is believed to determine the unique three-dimensional conformation in which the chains are folded. This conformation, which is necessary for the activity of the enzyme, is stabilized by interactions of amino acids in different parts of the peptide chains with each other and with the surrounding medium. These interactions are relatively weak and may be disrupted readily by high temperatures, acid or alkaline conditions, or changes in the polarity of the medium. Such changes lead to an unfolding of the peptide chains (denaturation) and a concomitant loss of enzymatic activity, solubility, and other properties characteristic of the native enzyme. Enzyme denaturation is sometimes reversible. See also Amino acids; Protein.

Many enzymes contain an additional, nonprotein component, termed a coenzyme or prosthetic group. This may be an organic molecule, often a vitamin derivative, or a metal ion. The coenzyme, in most instances, participates directly in the catalytic reaction. For example, it may serve as an intermediate carrier of a group being transferred from one substrate to another. Some enzymes have coenzymes that are tightly bound to the protein and difficult to remove, while others have coenzymes that dissociate readily. When the protein moiety (the apoenzyme) and the coenzyme are separated from each other, neither possesses the catalytic properties of the original conjugated protein (the holoenzyme). By simply mixing the apoenzyme and the coenzyme together, the fully active holoenzyme can often be reconstituted. The same coenzyme may be associated with many enzymes which catalyze different reactions. It is thus primarily the nature of the apoenzyme rather than that of the coenzyme which determines the specificity of the reaction. See also Coenzyme.

The complete amino acid sequence of several enzymes has been determined by chemical methods. By x-ray crystallographic methods even the exact three-dimensional molecular structure of a few enzymes has been deduced. See also X-ray crystallography.

Answer 2

The activities of enzymes are determined by their three-dimensional structure.[7]

Most enzymes are much larger than the substrates they act on, and only a very small portion of the enzyme (around 3–4 amino acids) is directly involved in catalysis.[8] The region that contains these catalytic residues and binds the substrate and then carries out the reaction is known as the active site. Some enzymes also contain sites that bind cofactors, which are needed for catalysis. Some enzymes also have binding sites for small molecules, which are often direct or indirect products or substrates of the reaction catalyzed. This binding can serve to increase or decrease the enzyme's activity, providing a means for feedback regulation.

Like all proteins, enzymes are made as long, linear chains of amino acids that fold to produce a three-dimensional product. Each unique amino acid sequence produces a unique structure, which has unique properties. Individual protein chains may sometimes group together to form a protein complex. Most enzymes can be denatured—that is, unfolded and inactivated—by heating, which destroys the three-dimensional structure of the protein. Depending on the enzyme, denaturation may be reversible or irreversible.

Answer 3

Enzymes are proteins and proteins consist of amino acids (there are 20 common amino acids) linked together "head to tail" by peptide bonds.

The peptide bonds are between 2 amino acids when the carboxylic acid group of one amino acid reacts with the amino group of the other amino acid.

The long chains of aamono acids form a protein which is then folded and wrapped around itself to form a 3D structure which has catalytic activity and can participate in biochemical reactions.

Answer 4

Enzymes are specialty proteins that make reactions go faster. They are composed of a string of amino acids just like any other protein. What makes them work is that the protein can fold into a specific configuration that allows the substrates to bind to it and enable reactions.

Answer 5

enzymes help break down food in the stomach and intestines. when you say chemical nature what are you asking?

Answer 6

they act as catalysts lowering the activation energy for a reaction. they also are being used in steriospecific reactions in pharmaceutical applications. enzymes are also the target of study so we can further understand how the body works.

Answer 7

They are polypeptides. Can you be more specific?