Abstract
The pre-steady-state kinetics for the hydrolysis of fructose 1, 6-bisphosphate by rabbit liver fructose bisphosphatase have been investigated by stopped-flow kinetics utilizing an acid-base indicator method that permits the continuous monitoring of the inorganic phosphate product. The reaction sequence is characterized by two successive first-order steps followed by establishment of the steady-state rate. The first exponential process results from a conformational change in the protein that is dye sensitive owing to a perturbation of an acidic residue on the protein. A second process reflects the rapid initial turnover of all four subunits of the enzyme with the concomitant release of inorganic phosphate followed by the rate-limiting step of the catalytic cycle. This latter step may involve a product release (fructose 6-phosphate) or a second conformational change. The catalytic cycle ends with decay of the enzyme to its initial unreactive resting state.
Original language | English (US) |
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Pages (from-to) | 830-835 |
Number of pages | 6 |
Journal | Biochemistry |
Volume | 18 |
Issue number | 5 |
DOIs | |
State | Published - 1979 |
All Science Journal Classification (ASJC) codes
- Biochemistry