Explore enzyme activity using cellobiase, a key enzyme associated with biofuel production.
The Biofuel Enzyme Reactions Kit for AP Biology is a student-driven, inquiry-based kit that characterizes the activity of the cellobiase enzyme. In this ThINQ! Investigation, students will play the role of bioengineer to explore the power of enzyme kinetics and optimize conditions that will maximize the rate of sugar conversion for the production of biofuel.
Students first extract cellobiase from mushrooms to discover one way that nature uses enzymes. They then generate questions and hypotheses about enzyme function under different environmental conditions — temperature, pH, and concentrations — that influence enzyme function. Students can take a structured, guided, or open approach to inquiry as they test their hypotheses. Finally, with data in hand, students use evidence to create a list of conditions for optimal enzymatic activity for biofuel production.
Timeline and Contents Overview
The flexible curriculum will fit within a broad range of available laboratory times. A possible arrangement is:
Cellulosic ethanol is a biofuel derived from plant matter. Cellulose is a polysaccharide found in the cell walls of plants; and cellobiose is a disaccharide constituent of cellulose. The breakdown of cellulose into smaller sugars is a multistep process that is facilitated by a family of enzymes called cellulases. Each cellulase has its own role in processing cellulose from a long strand of glucoses down to single units that can then undergo microbial fermentation to produce ethanol.
A key step in the production of cellulosic ethanol is the breakdown of cellobiose by the cellobiase enzyme. Students test and calculate the conversion rate of a sugar substrate (p–nitrophenyl glucopyranoside) to p–nitrophenol and glucose in the presence or absence of cellobiase.
Select the kit which is right for you and your students:
Standards alignment: AP Biology (ThINQ! Biofuel Kit); or General Biology, Biotechnology, CTE (Classic Biofuel Kit). Pedagogical support: Open, guided, and structured inquiry (ThINQ! Biofuel Kit); or Structured inquiry (Classic Biofuel Kit). Main learning objective: Focus on student-driven questions and problem solving (ThINQ! Biofuel Kit); or Mastery of technical skills (Classic Biofuel Kit). Initial experiment: Compare reaction rates of mushroom extracts (ThINQ! Biofuel Kit); or Compare reaction rates with and without purified enzyme (Classic Biofuel Kit). Initial experiment cont.: Focuses on inquiry process (ThINQ! Biofuel Kit); or Uses well characterized samples to obtain reproducible results (Classic Biofuel Kit). Kit contents (for both ThINQ! Biofuel and Classic Biofuel Kits): Materials for 8 student workstations to perform 1 initial experiment and up to 5 additional enrichment activities.