Fructokinase
| Fructokinase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 Fructokinase dimer, Bacillus subtilis | |||||||||
| Identifiers | |||||||||
| EC no. | 2.7.1.4 | ||||||||
| CAS no. | 9030-51-7 | ||||||||
| Databases | |||||||||
| BRENDA | enzyme data | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | enzyme entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| Rhea | reactions | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| |||||||||
Fructokinase (EC 2.7.1.4), also known as D-fructokinase, is an enzyme that transfers a phosphate group from adenosine triphosphate (ATP) to D-fructose, producing D-fructose 6-phosphate.[1] Its systematic name is ATP:D-fructose 6-phosphotransferase.[1] In enzyme nomenclature, it is distinct from ketohexokinase (EC 2.7.1.3), which instead produces D-fructose 1-phosphate.[2]
Role in plants and bacteria
[edit]Fructokinase has been characterized from various organisms, such as pea (Pisum sativum) seeds, avocado (Persera americana) fruit, and maize (Zea mays) kernels, and many more.[3]
Specifically, fructokinase may also regulate starch synthesis in conjunction with sucrose synthase.[3] There are also two divergent fructokinase genes that are differentially expressed and which also have different enzymatic properties such as those found in tomatoes. In tomatoes, fructokinase 1 (Frk 1) mRNA is expressed at a constant level during fruit development. However, fructokinase 2 (Frk 2) mRNA has a high expression level in young tomato fruit but then decreases during the later stages of fruit development. Frk 2 has a higher affinity for fructose than Frk 1 but Frk 2 activity is inhibited by high levels of fructose, whereas Frk 1 activity is not.[3]
In Sinorhizobium meliloti, a common gram-soil bacterium, fructokinase is also used in the metabolism of mannitol and sorbitol, in addition to the metabolism of fructose.[4]
Reaction
[edit]Fructokinase catalyzes the following reaction:[1]
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See also
[edit]References
[edit]- 1 2 3 "EC 2.7.1.4". IUBMB Enzyme Nomenclature. International Union of Biochemistry and Molecular Biology. Retrieved 10 September 2026.
- ↑ "EC 2.7.1.3". IUBMB Enzyme Nomenclature. International Union of Biochemistry and Molecular Biology. Retrieved 10 September 2026.
- 1 2 3 Odanaka S, Bennett AB, Kanayama Y (July 2002). "Distinct physiological roles of fructokinase isozymes revealed by gene-specific suppression of Frk1 and Frk2 expression in tomato". Plant Physiol. 129 (3): 1119–26. doi:10.1104/pp.000703. PMC 166506. PMID 12114566.
- ↑ Gardiol A, Arias A, Cerveñansky C, Gaggero C, Martínez-Drets G (October 1980). "Biochemical characterization of a fructokinase mutant of Rhizobium meliloti". J. Bacteriol. 144 (1): 12–6. doi:10.1128/jb.144.1.12-16.1980. PMC 294576. PMID 6252186.
External links
[edit]- Fructokinases at the U.S. National Library of Medicine Medical Subject Headings (MeSH)
