Interaction with Enzymes

Interaction with enzymes usually involves inhibition, but enzyme induction also has its uses, or can occur unintentionally. Interactions generally occur by binding at the active site of the enzyme (where the substrate binds), in a very similar manner to receptor binding - the comments below, concerning receptors, can equally apply to enzyme interactions with drugs. 

---

The UV spectra of 1- and 3-deazaflavins have been measured 74JCS(P1U965, 78B1942), and used in the latter instance in a study of their interaction with enzymes 79B3635). 

Proteins embedded in the shell of lipoproteins. They serve as scaffold for assembly of the lipoprotein particle in the endoplasmic reticulum. In addition, they control metabolism of lipoproteins in the circulation by interaction with enzymes such as lipases. Finally, apolipoproteins determine cellular uptake of the particles by interaction with specific lipoprotein receptors expressed on the surface of target cells. 

It is worth noting here that inhibitors that interact with enzyme active site functionalities in ways that mimic the structure of covalent intermediates of catalysis can bind with very high affinity. This was seen in Chapter 1 with the example of statine-and hydroxyethylene-based inhibitors of aspartic proteases other examples of this inhibitor design strategy will be seen in subsequent chapters of this text. 

Reversible Modes of Inhibitor Interactions with Enzymes... 

Figure 3.2 Cartoon representations of the three major forms of reversible inhibitor interactions with enzymes (A) competitive inhibition (B) noncompetitive inhibition (C) uncompetitive inhibition. Source-. From Copeland (2000).

Often high-affinity, or tight binding, interactions with enzymes is the result of a very slow dissociation rate of the enzyme-inhibitor binary complex. 

Naturally-occurring food legume tannins are reported to interact with enzyme and non-enzyme proteins to form complexes that... 

Enzymes There are many different types of enzymes in the human body. They are required for a variety of functions. Drugs can interact with enzymes to modulate their enzymatic activities. 

Drugs interact with enzymes and receptors mainly through van der Waals forces and hydrogen bonding they need the correct shapes and sizes to fit into the active sites of the targets. 

As described for receptor interactions, enantioselectivity may also be manifested in drug interactions with enzymes and transport proteins. Enantiomers may display different affinities and reaction velocities. 

---