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Purified E. histolytica amylases III to VI were characterized by their hydrolytic behaviour towards 4-nitrophenyl a-malto-oligosaccharides, malto-oligosaccharides, amylose, amylopectin, glycogen and Y-cyclodextrin. The influence of specific inhibitors on the amylase activity of E. histolytica was examined and compared with typical a-and ß-amylases.Amylases III and IV showed -glucosidase and glucosyltransferase activity by cleaving terminal non-reducing glucose from pNPGj (III, IV) and pNPG 2 to pNPG 7 (III). Both enzymes were able to cleave malto-oligosaccharides and glucopolysaccharides to a large number of malto-oligosaccharides. Also transglucosidation reactions were observed, but maltose was not hydrolysed. Amylase V showed exoamylase-like properties by preferentially cleaving maltose units from the non-reducing end of synthetic and biogenic malto-oligosaccharides by a multiple-attack mechanism. Amylase VI was characterized as an -amylase, showing great similarities with porcine pancreatic -amylase in the hydrolysis pattern of 4-nitrophenyl a-malto-oligosaccharides and glucopolysaccharides. With biogenic malto-oligosaccharides amylase VI showed a transglucosidation reaction. Trennung und Charakterisierung von vier Amy lasen aus Entamoeba histolytica. II. Charakterisierung der Amy lasenZusammenfassung: Gereinigte Amylasen III bis VI aus Entamoeba histolytica wurden aufgrund ihres hydrolytischen Verhalten gegenüber 4-Nitrophenyl-a-maltooligosacchariden, Maltooligosacchariden, Amylose, Amylopektin, Glycogen and Y-Cyclodextrin charakterisiert. Der Einfluß spezifischer Inhibitoren auf die Amylaseaktivität aus E. histolytica wurde untersucht und mit