Transfructosylation of thiol group by beta-fructofuranosidases.
Beta-fructofuranosidase fructosylated not only the hydroxyl group but also the thiol group of 2-mercaptoethanol in a transfer reaction using sucrose as a donor substrate. The enzymes from Candida utilis and Saccharomyces cerevisiae (bakers' yeast) were effective catalysts for the thio-fructofuranosylation. The thio-fructosylation product was isolated by activated carbon chromatography and its structure was confirmed by Fab-mass spectrometry and NMR spectroscopy. The thio-fructofuranoside was synthesized effectively at around 3.0 M for the acceptor concentration. The product increased with the sucrose concentration at least up to 1.9 M. O-Fructofuranoside was simultaneously synthesized at an early stage of the reaction, although it was hydrolyzed on further incubation. On the contrary, the thio-fructofuranoside accumulated efficiently after synthesis, indicating it was very stable against the hydrolytic action of the beta-fructofranosidase.
Nakano
H
H
Osaka Municipal Technical Research Institute, Japan. nakanohi@city.osaka.jp
Murakami
H
H
Shizuma
M
M
Kiso
T
T
de Araujo
T L
TL
Kitahata
S
S
D002236:Carbohydrate Conformation; D005632:Fructose / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D008623:Mercaptoethanol / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*; D013395:Sucrose / Q000378:metabolism; D043324:beta-Fructofuranosidase
D005632:Fructose; D013395:Sucrose; D008623:Mercaptoethanol; D006026:Glycoside Hydrolases; D043324:beta-Fructofuranosidase