🧬AP Biology
3. Many industrial laundry detergents contain proteases, enzymes that break down protein-based stains. Scientists are investigating the effectiveness of a novel protease, Protease T, isolated from a thermophilic bacterium found in hot springs (average temperature 75°C), compared to a standard protease, Protease S, isolated from a soil bacterium (average temperature 20°C).
In the experiment, identical fabric swatches stained with egg yolk were placed in beakers containing a pH-neutral buffer solution. Protease T was added to half the beakers, and Protease S was added to the other half. The beakers were incubated at temperatures of 20°C, 40°C, 60°C, and 80°C for 30 minutes. The scientists then measured the percentage of the stain removed from each swatch to determine enzyme activity.
Describe how the sequence of amino acids determines the specific three-dimensional shape of a protein like a protease.
Justify why the scientists incubated the fabric swatches for exactly 30 minutes at each temperature rather than using different time intervals across the different temperatures.
Predict the specific pattern of results (in terms of percentage of stain removed) you would expect for Protease S across the four temperature conditions (20°C, 40°C, 60°C, and 80°C) if enzyme activity is dependent on optimal temperature for this mesophilic protease.
Justify your prediction from Part C by explaining, based on the chemical properties of proteins, why Protease S activity would decrease or become ineffective at 80°C while Protease T, from a thermophilic bacterium, would remain effective at this temperature.
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