Granule Bound Starch Synthase (GBSS) refers to an enzyme involved in the synthesis of starch in plants. It is primarily located in the amyloplasts, which are specialized organelles responsible for starch granule formation. GBSS plays a crucial role in catalyzing the elongation of polysaccharides during starch biosynthesis.
GBSS is part of a larger family of enzymes known as starch synthases, which are responsible for the synthesis of starch granules. It specifically acts on glucose molecules to form linear chains, which are then further branched by other enzymes. GBSS works in cooperation with other starch synthases and enzymes involved in the regulation of starch biosynthesis to ensure proper starch granule formation and structure.
Through the process of granule-bound starch synthesis, GBSS controls the size and composition of starch granules. The enzyme utilizes ADP-glucose as a substrate, which is converted into glucose molecules and incorporated into growing starch chains. By controlling the incorporation of glucose molecules, GBSS influences the overall composition and properties of starch.
Mutations or deficiencies in GBSS can lead to alterations in starch composition, resulting in various phenotypes in plants. For example, deficiencies in GBSS can lead to the synthesis of amylose-only starch, which has implications for plant growth and development.
In summary, Granule Bound Starch Synthase is an enzyme involved in starch synthesis, playing a key role in the elongation of polysaccharides during starch granule formation. It contributes to the composition and structure of starch granules and is essential for normal plant growth and development.
