Abstract
Rapid quench kinetic experiments on fructose 1,6-bisphosphatase demonstrate a stereospecificity for the α anomer of fructose 1,6-bisphosphate relative to the β configuration. The β anomer is only utilized after mutarotation to the α form in a process that is not enzyme catalyzed. Studies employing analogues of the acyclic keto configuration indicate that the keto form is utilized at a rate less than 5% that of the α anomer, a finding also confirmed by computer simulation of the rapid quench data. Chemical trapping experiments of the keto analogue, xylulose 1,5-bisphosphate, and the normal substrate suggest that interconversion of the acyclic and anomeric configurations is retarded by their binding to the enzyme. A hypothesis is advanced attributing substrate inhibition of fructose 1,6-bisphosphatase to possible binding of the keto species.
Original language | English (US) |
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Pages (from-to) | 2479-2484 |
Number of pages | 6 |
Journal | Biochemistry |
Volume | 16 |
Issue number | 11 |
DOIs | |
State | Published - May 1 1977 |
All Science Journal Classification (ASJC) codes
- Biochemistry