Premium
Chemoenzymatic Syntheses of Linear and Branched Hemithiomaltodextrins as Potential Inhibitors for Starch‐Debranching Enzymes
Author(s) -
Greffe Lionel,
Jensen Morten T.,
ChangPiHin Florent,
Fruchard Sandra,
O'Donohue Michael J.,
Svensson Birte,
Driguez Hugues
Publication year - 2002
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/1521-3765(20021202)8:23<5447::aid-chem5447>3.0.co;2-h
Subject(s) - glycogen debranching enzyme , enzyme , biochemistry , chemistry , starch , glycogen synthase
Oligosaccharides embodying the S ‐maltosyl‐6‐thiomaltosyl structure have been readily synthesised by using convergent chemoenzymatic approaches. The key steps for the preparation of these molecules involved: 1) transglycosylation reactions of maltosyl fluorides onto suitable acceptors catalysed by the bacterial transglycosylase, cyclodextrin glycosyltransferase (CGTase), and 2) the S N 2‐type displacement of a 6‐halide from acetylated acceptors by activated 1‐thioglycoses. The target molecules, which were obtained in good overall yields, proved to be useful for investigating substrate binding in the active sites of several enzymes that act upon the α ‐1,6‐linkage of pullulan and/or amylopectin. The compounds exhibit K i values in the 2.5–1350 μ M range with the different enzymes, and the highest affinity found by using these molecules was seen for the pullulanase from Bacillus acidopullulyticus. Both barley‐malt limit dextrinase and pullulanase type II from Thermococcus hydrothermalis only recognised the longest linear thiooligosaccharide, while a branched heptasaccharide was the strongest inhibitor of pullulanase from Klebsiella planticola.