Schematic model of beta-amylase multiple attack mechanism
Glucose units are show as a hexagons and the horizontal lines between hexagons are alfa-1,4-glucosidic bonds. Points of alfa-amylase attack are shown as red arrows. Reducing end of amylose is represented by left side of animation.
Types of possible actions:
- productive attack of alfa-amylase:
- initial attack - make the enzyme-substrate complex. For beta-amylase only attack to alfa-1,4-glucosic bond between second and third glucose unit from nonreducing end is productive.
- multiple attack - produces maltoses by sliding of the enzyme along the amylose without dissociation enzyme-substrate complex.
- nonproductiwe attack of alfa-amylase - without hydrolysing alfa-1,4-bounds in poliglucose chains.