Biochemistry Lab: Invertase Kinetics and Assay Vocabulary

Vocabulary terms and key definitions covering enzyme kinetics, spectrophotometry principles, and laboratory procedures from the invertase lab lecture.

WSG

Worthington Stadtgne Glucose; a reagent mixture containing glucose oxidase, peroxidase, and odialisidine used to form a colored complex for measuring glucose concentration.

Invertase

A yeast enzyme that catalyzes the hydrolysis of sucrose into glucose and fructose.

Glucose Oxidase

An enzyme that acts on glucose to form hydrogen peroxide and gluconic acid.

Peroxidase

An enzyme that breaks down hydrogen peroxide in the presence of a colored reagent (odialisidine) to produce a colored complex.

Beer's Law

A physical law stating that absorbance is equal to the path length times concentration times the molar extinction coefficient.

Assay Wavelength

The spectrophotometer setting of $500\,\text{nm}$ used to measure the absorbance of the colored WSG complex.

Blank

A reference test tube containing zero glucose ($0\,\text{mM}$) used to zero or calibrate the reaction readings.

Sulfuric Acid ($H_2SO_4$)

A reagent added in $8\,\text{mL}$ volumes to rapidly stop the enzyme reaction at designated time intervals.

95% Ethanol

A solution prepared by mixing $95\,\text{mL}$ of ethanol in a total volume of $100\,\text{mL}$ with water.

Vortex

A laboratory mixer used to quickly and thoroughly mix liquid contents within test tubes.

Tested Enzyme Inhibitors

The two specific inhibitors used in Part B of the experiment: potassium chloride and fructose.