The site to which regulator binds.

The substance that attaches to the allosteric enzyme.

Enzymes that are regulated through allosteric regulation.

Enzymes are often referred to as:

Which type of proteins are highly effective biological catalysts?

Enzymes can accelerate chemical reactions in cells by approximately how much compared to uncatalyzed reactions?

What is the primary composition of most enzymes?

Which naming convention is commonly used for enzymes that are named after the substrate they act on?

They are not consumed or used up in chemical reactions.

1. They catalyze a particular chemical reaction with a high degree of specificity.

Enzymes chemically recognize, bind, and modify substrates through:

What can disrupt the three-dimensional structure of enzymes and render them inactive?

Non-protein molecules or ions that enzymes often require for their catalytic activity.

A type of enzyme that consists only of a protein component.

A type of enzyme that consists of both a protein and a non-protein component that require each other for enzymatic function.

The protein part of a conjugated enzyme.

The non-protein part of a conjugated enzyme.

The protein component of an enzyme that lacks its cofactor or coenzyme, making it inactive until it binds with the necessary non-protein molecule to form the active conjugated enzyme.

A non-protein molecule that assists an enzyme in performing its catalytic function through participating in the chemical reactions it facilitates by providing specific chemical groups or aiding in substrate binding.

A high molecular weight compounds made up principally of chains of amino acids linked together by peptide bonds.

A tightly bound small organic molecule or inorganic metal ion that is an integral part of an enzyme's structure that facilitates enzyme-substrate interactions and catalyzing chemical reactions.

Enzymes are primarily named based on their ____, which is a reflection of the specific chemical reactions they facilitate in biological processes.

Enzymes are named after the substance, known as the ____, that they act upon in the chemical reaction.

Enzyme that catalyze hydrolysis reactions, which involve the breaking of chemical bonds by the addition of a water molecule.

The enzyme responsible for catalyzing the hydrolysis of lactose, breaking it down into its constituent sugars.

A digestive enzyme that plays a key role in breaking down proteins in the stomach.

A digestive enzyme that further break down proteins into smaller peptides and amino acids.

An enzyme derived from the papaya fruit.

catalyzes the hydrolysis of sucrose

catalyzes the hydrolysis of lipids

catalyze oxidation

catalyze hydrolysis

Naming of Enzyme:

These enzymes are involved in the transfer of electrons, often in the form of hydride ions (H-) or hydrogen atoms (H), from one molecule to another.

Enzymes responsible for group transfer reactions.

Enzymes that can either add groups to double bonds or remove groups to create double bonds in molecules.

Enzymes that facilitate the transfer of functional groups within molecules, leading to the conversion of one isomeric form into another.

Enzymes that are responsible for the formation of covalent bonds between molecules by condensation reactions coupled to ATP cleavage.

A selected subclass of oxidoreductases that catalyze oxidation reactions, specifically the removal of electrons from a substrate.

A selected subclass of oxidoreductases that catalyze reduction reactions, which involve the addition of electrons to a substrate.

A selected subclass of oxidoreductases that catalyze reactions in which a double bond is introduced through the formal removal of two hydrogen atoms from a substrate.

A selected subclass of Transferases that catalyze the transfer of an amino group (NH2) from one molecule to another.

A selected subclass of Transferases that catalyze the transfer of a phosphate group from a molecule containing a high-energy phosphate bond (usually ATP) to another molecule, which becomes phosphorylated as a result.

A selected subclass of Hydrolases that catalyze the hydrolysis of ester linkages in lipids.

A selected subclass of Hydrolases that catalyze the hydrolysis of amide linkages in proteins.

A selected subclass of Hydrolases that catalyze the hydrolysis of sugar-phosphate ester bonds in nucleic acids.

A selected subclass of Hydrolases that catalyze the hydrolysis of glycosidic bonds in carbohydrates.

A selected subclass of Hydrolases that catalyze the hydrolysis of phosphate-ester bonds.

A selected subclass of lyases that catalyze the removal of H2O (water) from the substrate.

A selected subclass of lyases that catalyze the removal of CO₂ (carbon dioxide) from the substrate.

A selected subclass of lyases that catalyze the removal of NH3 (ammonia) from the substrate.

A selected subclass of lyases that catalyze the addition of H2O (water) to the substrate.

A selected subclass of isomerases that catalyze racemization reactions: conversion of D to L isomer, or versa.

A selected subclass of isomerases that catalyze mutational reactions that involve the transfer of a functional group from one position to another within a molecule.

A selected subclass of ligase that catalyze formation of new bond between two substrates, with participation of ATP.

A selected subclass of ligase that catalyze formation of new bond between a substrate and CO2, with participation of ATP.

How ENZYMES work:

Enzymes are highly specific:

It has a 3-dimensional shape that precisely matches the 3-dimensional shape of the molecule to be reacted.

When the substrate and enzyme bind temporarily, an ____ is formed.

In an enzymatic reaction, the activation energy needed for the reaction to occur is reduced.

It describes how enzymes and substrates interact in a highly specific manner, where the substrate's 3D shape matches the complementary shape of the enzyme's active site, allowing for efficient chemical reactions.

It describes how enzymes undergo conformational changes when they interact with their substrate, allowing for a better alignment of the enzyme's active site with the substrate, facilitating the catalytic reaction.

A non-protein organic substance which is dialyzable, thermostable and loosely attached to the protein part.

An organic substance which is dialyzable and thermostable which is firmly attached to the protein or apoenzyme portion.

A substance that enhances the activity of enzymes or other biological molecules by binding to specific sites and facilitating chemical reactions, such as K+ , Fe2+, Fe3+, Cu2+ , Co2+, Zn2+, Mn2+, Mg2+, Ca2+, and Mo3+ .

An inactive enzyme

Temperature and Enzyme Activity

pH and Enzyme Activity

Substrate Concentration and Enzyme Activity

Enzyme Concentration and Enzyme Activity

Formation of an enzyme-substrate complex as an intermediate species provides an alternative pathway, with lower activation energy, through which a reaction can occur.

The active site has a fixed geometric shape. Only a substrate with a matching shape can fit into it.

The active site has a flexible shape that can change to accept a variety of related substrates. Enzymes vary in their degree of specificity for substrates.

Reaction rate increases with ____ until the point at which the protein is denatured and activity drops sharply.

Maximum enzymatic activity is possible only within a ____ pH range: outside this pH range, the protein is denatured and activity drops sharply.

Reaction rate increases with ____ until full saturation occurs; then the rate levels off.

Reaction rate increases with increasing ____ , assuming ____ is much lower than that of the substrate.

It states that when the rate or velocity of the reaction is examined under varying substrate concentrations:

If the rate or velocity of the reaction is plotted against the substrate concentration, the resulting curve is ____.

The substrate concentration at half maximal velocity (rate of reaction).

A type of enzyme inhibition where an inhibitor molecule can bind to an enzyme and then dissociate from it, allowing the enzyme's activity to recover when the inhibitor is removed.

Occurs when an inhibitor molecule competes with the substrate for binding to the enzyme's active site, reducing the enzyme's ability to catalyze the reaction.

Occurs when an inhibitor binds to an allosteric site on the enzyme, altering the enzyme's shape and reducing its activity. This type of inhibition can be reversible or irreversible, depending on the specific mechanism.

2. Takes place when the inhibitor only binds to the enzyme-substrate complex, preventing the release of the product, which results in decreased enzyme activity.

Substances that bind to an enzyme and stop or slow its normal catalytic activity.

A molecule closely resembling the substrate. Binds to the active site and temporarily prevents substrates from occupying it, thus blocking the reaction.

A molecule that binds to a site on an enzyme that is not the active site. The normal substrate still occupies the active site but the enzyme cannot catalyze the reaction due to the presence of the inhibitor.

A molecule that forms a covalent bond to a part of the active site, permanently preventing substrates from occupying it.

There are two main reasons why an enzyme is regulated:

An enzyme regulation in which the product inhibits one of the reactions in a chain of enzyme-catalyzed reactions.

In order to activate these enzymes, a small part of their polypeptide chain must be removed.

Produced in its inactive form rather than in its active form to avoid random reactions in the body.

Proenzyme are generally activated by the substrate of the pathway and inhibited by the product of the pathway, thus only turning the pathway on when it is needed. This process is known as ____.

Enzymes that catalyzes the breaking of peptide bonds.

This regulation happens when a substance binds to a certain part of the enzyme (but not in its active site) and changes the shape of its active site.

A regulator may inhibit the enzyme action (negative modulation) or may stimulate the enzyme action (positive modulation).

When a small molecule can act as an effector or regulator to activate or inactivate an action of a protein:

Allosteric enzymes has two kinetic states :

This is the less active form of the enzyme

Allosteric enzymes has two kinetic states :

This is more active form of the enzyme