What type of compounds are enzymes

The substrate oxidized is regarded as a hydrogen or electron donor. The classification is based on 'donor:acceptor oxidoreductase'. The common name is 'dehydrogenase', wherever this is possible; as an alternative, 'acceptor reductase' can be used. Classification is difficult in some cases, because of the lack of specificity towards the acceptor.

Transferases: Transferases are enzymes that transfer a group, for example, the methyl group or a glycosyl group, from one compound generally regarded as donor to another compound generally regarded as acceptor. The classification is based on the scheme 'donor:acceptor grouptransferase'. The common names are normally formed as 'acceptor grouptransferase' or 'donor grouptransferase'.

In many cases, the donor is a cofactor coenzyme that carries the group to be transferred. The aminotransferases constitute a special case. Hydrolases: These enzymes catalyse the hydrolysis of various bonds. Some of these enzymes pose problems because they have a very wide specificity, and it is not easy to decide if two preparations described by different authors are the same, or if they should be listed under different entries.

While the systematic name always includes 'hydrolase', the common name is, in most cases, formed by the name of the substrate with the suffix -ase. It is understood that the name of the substrate with this suffix, and no other indicator, means a hydrolytic enzyme. It should be noted that peptidases have recommended names rather than common names. They differ from other enzymes in that two or more substrates are involved in one reaction direction, but there is one compound fewer in the other direction.

When acting on the single substrate, a molecule is eliminated and this generates either a new double bond or a new ring. The systematic name is formed according to 'substrate group-lyase'.

In common names, expressions like decarboxylase, aldolase, etc. In cases where the reverse reaction is the more important, or the only one to be demonstrated, 'synthase' may be used in the name. Ligases: Ligases are enzymes that catalyse the joining of two molecules with concomitant hydrolysis of the diphosphate bond in ATP or a similar triphosphate. Activating Transcription Factor. Adenylate Kinase. Alkaline Phosphatase.

Aurora Kinase. Beta Lactamase. Calcium and Integrin Binding. Carbonic Anhydrase. Casein Kinase. Creatin Kinases. Cyclin-Dependent Kinase. Discoidin Domain Receptor Tyrosine Kinase. DNA Polymerase. EGF Receptor. FGF Receptors. FK Binding Protein. Fructosamine 3 Kinase. Glycogen synthase kinase. Guanylate Kinase. Histone Deacetylase. Jun N-terminal Kinase. Jun Proto-Oncogene. Mitogen-Activated Protein Kinase. Natural Enzymes. Nudix Type Motif. They are high molecular weight compounds made up principally of chains of amino acids linked together by peptide bonds.

See Figure 1. Enzymes can be denatured and precipitated with salts, solvents and other reagents. They have molecular weights ranging from 10, to 2,, Many enzymes require the presence of other compounds - cofactors - before their catalytic activity can be exerted. This entire active complex is referred to as the holoenzyme; i.

A coenzyme - a non-protein organic substance which is dialyzable, thermostable and loosely attached to the protein part. A prosthetic group - an organic substance which is dialyzable and thermostable which is firmly attached to the protein or apoenzyme portion.

PDF version of Introduction to Enzymes. Introduction to Enzymes Video.