Study Set Content:
Models of catalysis
Lock and key versus induced-fit
which the substrate behaves as a key that fits into a lock, the enzyme.
Lock and Key
The first attempt at explaining this process led to the
Lock and Key
overcomes some of the limitations of the Lock and Key Model.
Induced fit model
The Lock and Key Model, to a certain degree, explains the specificity of
enzymes
n this model, the substrate still needs to fit into the enzyme like a key, but instead of simply fitting into the “keyhole,” some type of modification is induced in the substrate, enzyme, or both.
Induced fit model
Just as only the right key will fit into a lock, only the right (blank) fits into the enzyme
susbtrate
One limitation of the Lock and Key Model is that it does not explain why the reaction actually
occurs
One limitation of the Lock and Key Model is that it does not explain why the reaction actually occurs, and another is that enzymes are (blank) as this theory implies
flexible and not rigid
Enzyme activity is regulated by five mechanisms:
A. Feedback control
B. Proenzymes
C. Allosterism
D. Protein modification
E. Isoenzymes
his is an enzyme regulation process in which formation of a product inhibits an earlier reaction in the sequence.
Feedback control:
Feedback control
some enzymes in the body are manufactured in an inactive form. To make them active, a small part of their polypeptide chain must be removed.
Proenzymes/Zymogens:
Prothrombin
Zymogens
Thrombin
Acive enzymes
Chymotrypsinogen
Zymogens
Trypsinogen
Zymogens
Chymotrypsin
Active enzymes
Trypsin
Active enzymes
Pepsin
Active enzymes
