Enzymes Flashcards
Enzyme
An enzyme is a protein that has an active site which speeds up the reaction time of a reaction by reducing the energy needed to achieve equilibrium.
Substrate
A substrate is the product that goes into the enzyme to be reacted. It has a very specific shape and only it can fit into the the active site of a specific protein.
Catalyst
An enzyme works as a catalyst for chemical reaction by reducing the energy needed to achieve equilibrium without itself undergoing permanent changes.
Enzyme-substrate complex
The complex of the enzyme and the substrate together is known as the enzyme-substrate complex
Lock and key model
This model describes an enzyme and its substrate as a lock and key. Only a very specific key can go into the lock and open it. This is similar to an enzyme because the enzyme is very compound specific.
Immobilized Enzyme
Immobilized enzymes are attached to inert, insoluble material which can provided increased resistance to pH changes and temperature changes. This essentially means the enzyme will stay in the system and continue to catalyze reactions without being washed away or take out through some process.
Vmax
The maximum rate or reaction rate achieved when using an enzyme. The concentration of the substrate also influences how many reactions can occur in a system.
Protease
A protease is an enzyme that breaks down protein products. This happens by hydrolysis of the peptide bonds.
Chymotrypsin
A digestive enzyme that breaks down proteins in the small intestine. Chymotrypsin cleaves the peptide bonds preferentially where there are hydrophobic side chains, large aromatic rings that fit into the active site. These include tyrosine, tryptophan, and phenylalanine. It is activated in the presence of trypsin.
Trypsin
This is a protease that has a serine in the active site to act as a nucleophile. Trypsin cleaves peptide bonds at the carboxyl side of lysine and arginine.
Serine protease
Serine protease are enzymes that have serine in their active sites to act as nucleophiles. Trypsin is a serine protease
Pepsin
This is a protein cleaving enzyme that is made in the stomach. It cleave polypeptide chains inside the chain as it is an endopeptidase. Its active cite uses aspartate and water molecules to cleave the peptide bonds. It is the main protein digesting enzymes in the digestive system.
zymogen
Also called a proenzyme is a non-active precursor to an enzyme. This is the enzyme but it is inactive because the active site is closed off. When an environmental factor comes along it can open up the active site
Chymosin
Another name for rennin
Rennin/Rennet
This is a protease endopeptidase that has aspartic acid in the active site. The enzyme cleaves the casein protein in a specific location which produces para-casein. This causes the hydrophobic groups to aggregate together and this produces the curd.
