Enzymes are highly specific and can distinguish isomers of the same molecule. The enzyme invertase specifically catalyzes the reaction of the conversion of sucrose to its individual carbohydrates glucose and fructose. It does not catalyse the reaction of maltose to 2 glucose or lactose to galactose. In this experiment, titrimetric and spectrophotometric methods were used to determine the specificity of invertase by determining the amount of glucose converted from the given disaccharides. The results show that sucrose yielded the least amount of glucose and got the lowest absorbance reading.
INTRODUCTION
Enzymes are globular proteins. Their folded conformation creates an area known as the active site. The nature and arrangement of amino acids in the active site make it specific for only one type of substrate.
Enzymes catalyze an unfathomable number of reactions by using a combination of only six basic mechanisms: (1) acid-base catalysis; (2) covalent catalysis; (3) metal ion catalysis; (4) electrostatic catalysis; (5) proximity and orientation effects; and (6) preferential binding of the transition state complex. Independent of the mechanistic characteristics taken to generate product, the initial reaction rates of every enzyme can be analyzed in order to quantify their overall efficiency.
Enzymes are specific for:
a) substrate
b) reaction It means that they catalyze the transformation of just one substrate or a family of substrates that are structurally related, catalyzing only one of the possible reactions of the substrate(s). The enzyme specificity of action is related to the fact that the enzyme only catalyzes one of the possible transformations of a substrate.
Invertase is beta-fructofuranosidase (EC3.2.1.26), which implies that the reaction catalyzed by this enzyme is the hydrolysis of the terminal nonreducing beta-fructofuranoside residues in beta-fructofuranosides.
The objective of this experiment is to investigate specificity of
References: [1] Berg, Jeremy M., Tymoczko, John L., and Stryer, Lubert. Biochemistry. 6th ed. (2007) New York, N.Y.: W.H. Freeman and Company.