To reiterate, unlike allosteric modulation, which involves noncovalent binding of modulator molecules, covalent modulation requires chemical reactions in which covalent bonds are formed. Most chemical reactions in the body are mediated by a special class of proteins known as enzymes, whose properties will be discussed in Section B of this chapter.
Post-translational modification (PTM) refers to the covalent and generally enzymatic modification of proteins following protein biosynthesis.Proteins are synthesized by ribosomes translating mRNA into polypeptide chains, which may then undergo PTM to form the mature protein product. PTMs are important components in cell signaling, as for example when prohormones are converted to hormones.
modulation [mod″u-la´shun] the normal capacity of cell adaptability to its environment. antigenic modulation the alteration of antigenic determinants in a living cell surface membrane following interaction with antibody. mod·u·la·tion (mod'yū-lā'shŭn), 1. The functional and morphologic fluctuation of cells in response to changing environmental ...
Covalent modulation. Activity of many enzymes is altered by the reversible making and breaking of a covalent bond between the enzyme and a small non-protein group. So covalent modification cause conformational changes in the enzymes. These conformational changes are brought about by covalent bonding of a phosphate group (phosphorylation) to the ...
The 2 mechanisms to alter protein shape are allosteric and covalent modulation. Allosteric: If the protein contains 2 binding sites, the noncovalent binding of a ligand to one site can alter the ...
modulation, in communications, process in which some characteristic of a wave wave, in physics, the transfer of energy by the regular vibration, or oscillatory motion, either of some material medium or by the variation in magnitude of the field vectors of an electromagnetic field (see electromagnetic radiation).
Covalent modulation synonyms, Covalent modulation pronunciation, Covalent modulation translation, English dictionary definition of Covalent modulation. n. 1. The act or process of modulating. 2. The state of being modulated. 3. Music a. A passing or transition from one key or tonality to another. b.
- [Voiceover] So today we're gonna learn about covalent modifications to enzymes. But first, let's review the idea that enzymes make reactions go faster. And looking at a reaction coordinate diagram you notice that enzymes do this by lowering the reaction's activation energy. Also, before we talk ...
The covalent attachment of another molecule can modify the activity of enzymes and many other proteins. In these instances, a donor molecule provides a functional moiety that modifies the properties of the enzyme. Most modifications are reversible. Phosphorylation and dephosphorylation are the most common but not the only means of covalent modification.