Amylopectin is a polysaccharide
with a varying structure; It is composed of linearly linked
alpha 1,4 linked
glucose units (coiled into tubular sections) with occasional
alpha 1-6 glycosidic bonds
which provide branching points.
Each amylopectin molecule may contain 100,000-200,000 glucose units, and each branch is about 20 or 30 glucose units in length, so that these molecules are bushy and nearly spherical in shape.
The many exposed ends can have more glucose units added to them by enzyme action for storage purposes or removed from them for use in respiration.
Amylopectin is one fraction of starch (typically 80-90%), the other fraction being amylose (10-20%).
Glycogen ("animal starch"), found in the liver and muscles, is effectively similar in structure to amylopectin, but it has shorter branches: 8-12 glucose units.
This simple model - specifically prepared for this website by the Sweet program - shows 84 glucose units.
The 1-4 linked sections can be seen to coil into a
, and the 1-6 linkage forms a
away from the main section ... return to original view