Fructose-1,6-bisphosphate aldolase (EC 4.1.2.13) is a glycolytic enzyme that catalyzes the reversible conversion of fructose-1,6-bisphosphate to glyceraldehyde 3-phosphate and dihydroxyacetone phosphate.
The enzyme is a tetramer of identical 40-kD subunits. Vertebrates have 3 aldolase isozymes, aldolase A (MIM.103850), B (ALDOB), and C (ALDOC; MIM.103870), which are distinguished by their electrophoretic and catalytic properties.
The sequence of the aldolases around the active-site lysine is highly conserved in evolution.
Mammalian tissues express aldolase isozymes in a well-characterized pattern.
Developing embryo produces aldolase A, which continues to be expressed in many adult tissues, sometimes at much higher levels than in embryo.
In adult muscle, aldolase A can be as much as 5% of total cellular protein. In adult liver, kidney, and intestine, aldolase A expression is repressed and aldolase B is produced.
In brain and other nervous tissue, aldolase A and C are expressed about equally. In transformed liver cells, aldolase A replaces aldolase B (Rottmann et al., 1984).
Pathology
germline mutations of the ALDOB gene in hereditary fructose intolerance (fructosemia) (MIM.229600).