Chemoenzymatic synthesis of branched oligo- and polysaccharides as potential substrates for starch active enzymes.

Oligo- and polysaccharides embodying the alpha-maltotriosyl-6(II)-maltotetraosyl structure were readily synthesized by transglycosylation of maltosyl fluoride onto panose and pullulan catalysed by the bacterial transglycosylase cyclodextrin glycosyltransferase (CGTase). The two products obtained proved useful for increasing the knowledge of substrate binding and processing at the active site of barley limit dextrinase that is involved in the metabolism of amylopectin by acting upon its branch points.