... subsite )2 and this subsite had the highest binding affinity among the glycone subsites [17], we investigated the role of Trp58 in the activity of HSAmy For this, mutants Trp58 fi Ala (W58A), Trp58 ... reason for the absence of binding at subsites in the crystal structure of acarbose-soaked human pancreatic a-amylase mutant D300N [12] It is known that a-amylases, can display transglycosylation activity ... During a transglycosylation reaction, the glycosyl covalent intermediate is Ó FEBS 2004 Trp58 mutants at subsite )2 of human salivary a-amylase (Eur J Biochem 271) 2525 chemistry for producing oligosaccharides...