All Flashcards
What is an enzyme?
A biological catalyst that speeds up chemical reactions in living organisms.
What is a catalyst?
A substance that speeds up a chemical reaction without being consumed in the reaction.
What is the active site of an enzyme?
The specific region of an enzyme where the substrate binds and catalysis occurs.
What is a substrate?
The reactant on which an enzyme acts to catalyze a chemical reaction.
What is induced fit?
A model describing how an enzyme changes shape upon substrate binding to create a better fit, enhancing catalysis.
What is enzyme specificity?
The ability of an enzyme to catalyze only certain reactions due to the unique shape of its active site.
What are the four levels of protein structure?
Primary: amino acid sequence; Secondary: alpha-helices and beta-sheets; Tertiary: overall 3D shape; Quaternary: arrangement of multiple polypeptide subunits.
Briefly describe the process of enzyme-substrate interaction.
Substrate binds to the enzyme's active site, forming an enzyme-substrate complex. The enzyme then catalyzes the reaction, converting the substrate into product(s).
Describe the induced fit model process.
Enzyme's active site is flexible. Substrate binds. Enzyme changes shape for tighter fit. Transition state forms more efficiently.
What are the differences between the 'lock and key' model and the 'induced fit' model of enzyme action?
Lock and Key: Enzyme active site is rigid and perfectly matches the substrate. | Induced Fit: Enzyme active site is flexible and changes shape to better fit the substrate.
What are the differences between the active site and allosteric site?
Active Site: Where substrate binds and reaction occurs. | Allosteric Site: Where a regulator molecule binds, affecting enzyme activity.