Molecular Cloning and Phylogenetic Analysis of Fructose-bisphosphate Aldolase (Cytoplasmic Isozyme) in Wheat, Barley and Rye

摘要

Fructose-bisphosphate aldolase (FBA, EC 4.1.2.13) catalyzes an aldol cleavage of fructose-1, 6-bisphosphate to dihydroxyacetone-phosphate and glyceraldehyde 3-phosphate and a reversible aldol condensation. Three candidate genes with 1077bp coding for fructose-bisphosphate aldolase were cloned and sequenced in wheat, barley and rye. These genes could encode 358 amino acid residues. Sequence analysis indicated that wheat, barley and rye FBA genes were conserved with high identity (94.13%), while maize sequence had a 9bp deletion near the 3' terminal. According to the alignment of 75 amino acid sequences, conserved domains of the FBAs were detected. These conserved domains might be the important functional sites of the FBAs. The cytoplasmic FBAs of wheat, barley and rye were clustered together, and the cluster was close to maize and rice FBAs. Nine peptides of the FBAs and the last amino acid Tyr (necessary for preference for fructose 1,6-bisphosphate over fructose 1-phosphate) were most conserved in plants, animals and algae. Current findings suggested that the FBAs could be divided into three main subgroups: plant cytoplasmic FBA, plant chloroplastic FBA and animal FBA. These results also indicated that the active and binding sites of FBAs had rare variations during the long-term evolution.