Computational analysis of the fructosyltransferase enzymes in plants, fungi and bacteria

Cloning, Expression and Characterization of a Novel Fructosyltransferase from Aspergillus oryzae ZZ-01 for the Synthesis of Sucrose 6-Acetate

“…Although we observed considerable differences in the primary structures and properties of r-AoFT and its homologs, the 3D structure of r-AoFT shared a similar core topology to most of the glycoside hydrolases belonging to glycoside hydrolase families 32 (GH32) 68 (GH68) [32,33]. The active site residue (Asp39) was located in the N-terminal fivefold β-propeller domain, where it could interact with the Gln57, Ser99 and Tyr282 residues located deep inside the central pocket of the β-propeller domain [1,31]. Several hydrogen bonding interactions were observed inside this active-site pocket between Asp39-Gln57, Asp39-Ser99, Ser99-Asp164 and Glu216-Tyr282 ( Figure 1B).…”

“…The sequence alignment of the representative r-AoFT proteins and their homologs revealed two conserved regions, including FRDPXVFW and CXXXECPX [1,31]. Although it has been predicted that the conserved acidic residues of r-AoFT could play a significant role in its catalytic activity, there have been no experimental data reported to date to confirm this speculation.…”

“…Similar results were observed for the other homologs from A. oryzae N74 and A. oryzae RIB40. Notably, the fructosyltransferase AoFT showed six potential N-glycosylation sites (N59, N107, N204, N261, N399 and N437) and six potential O-glycosylation sites (T324, T441, T443, T444, T445 and T516) (Supplementary Figure S1) [1,31]. It was deduced that the amino acid sequence of AoFT showed sequence identities of 98%, 96% and 90% with the fructosyltransferases from A. oryzae N74 (GU145136), A. oryzae RIB40 (XM_001823193) and A. nomius NRRL 13137 (XM_015553884).…”

“…Sucrose esters, which consist of a hydrophilic sucrose group and one to eight lipophilic fatty acid groups, are used in a wide variety of applications in the food, agricultural, cosmetic, detergent and pharmaceutical industries [1,2]. Sucrose 6-acetate (Suc6A) is a short-chain monoester and an important intermediate in the synthesis of sucralose, which is one of the sweetest sweeteners reported to date [3].…”

“…2.4.1.9) can be used to catalyze the cleavage of the β-(1,2)-glycosidic linkages between glucose and fructose units, as well as the transfer of the resulting fructosyl group from one sucrose unit to another [8][9][10]. FTase coding genes have been isolated from several species, including plants [11][12][13], fungi [1,8,14,15] and bacteria [16][17][18], where they encode for extra-or intracellular FTases representing the eight highly conserved motifs in the glycoside hydrolases belonging to glycoside hydrolase families 32 (GH32) and 68 (GH68) [1,19]. The majority of the ftase genes reported to date have been isolated from Aspergillus strains of fungi, although a recent database mining analysis identified ftase-related sequences in the genomes of Gibberella zeae, Magna porthe grisea and Ustilago maydis [19].…”