Chapter 9: Reaction Mechanisms, Pathways, Bioreactions and Bioreactors
Professional Reference Shelf
Example R9.6-3: Derive a Rate Law for a Multiple Substrate System
Derive the rate law for this sequence assuming that the rate of reaction
between the (ADH NADH)
complex and acetaldehyde is rate limiting. |
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| Solution | |||
| Assuming that the reaction between the cofactor-enzyme complex and acetaldehyde is rate limiting, the rate law is | |||
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| [Note: k2=k2
(h+).] After applying the PSSH
to (ES2)
and (E  )
to obtain the equations |
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(RE7.4-3.1) (RE7.4-3.2) |
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| we add Equations (RE7.4-3.1) and (RE7.4-3.2) and rearrange to obtain | |||
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(RE7.4-3.3) (RE7.4-3.4) | ||
| The total enzyme concentration is again constant at (Et): | |||
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(RE7.4-3.5) (RE7.4-3.6) | ||
| After solving Equation (RE7.4-3.6) for E, we combine with Equation (RE7.4-3.1) to obtain the rate law: | |||
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(RE7.4-3.7) | ||
| Setting P2 = 0 and rearranging, we obtain the initial rate law: | |||
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(RE7.4-3.8) | ||
| where | |||
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