Read the argument and complete the missing premise that makes the conclusion follow logically with absolute deductive certainty.
Answer:Biochemist: Any metabolic enzyme that requires zinc cofactor binding is structurally destabilized at temperatures exceeding 45°C. The newly isolated bacterial protease P-329 remains structurally stable at 50°C. Therefore, P-329 cannot catalyze peptide bond hydrolysis under physiological conditions.
The biochemist's conclusion follows logically if it is assumed that any metabolic enzyme that catalyzes peptide bond hydrolysis under physiological conditions 【requires zinc cofactor binding】.
The biochemist's conclusion follows logically if it is assumed that any metabolic enzyme that catalyzes peptide bond hydrolysis under physiological conditions 【requires zinc cofactor binding】.
Answer
requires zinc cofactor binding
The premises establish that protease P-329 remains stable at 50°C, which by contrapositive of the first premise proves that P-329 does not require zinc cofactor binding. The conclusion asserts that P-329 cannot catalyze peptide bond hydrolysis under physiological conditions. For this conclusion to follow necessarily, lacking zinc cofactor binding must be sufficient to prevent catalytic activity, meaning that requiring zinc cofactor binding is a necessary requirement for catalysis. Therefore, assuming that any enzyme that catalyzes peptide bond hydrolysis requires zinc cofactor binding enables the valid deductive inference: Catalyzes Hydrolysis -> Requires Zinc -> Destabilized >45°C. Since P-329 is stable at 50°C, it cannot require zinc, and thus cannot catalyze hydrolysis.
Step-by-Step Solution
Key Concept
Sufficient Assumption Deductive Bridging