Glykokalyksia

Glykokalyksia, commonly referred to as the glycocalyx, is a carbohydrate-rich layer that coats the exterior surface of many cell membranes. It is composed mainly of glycoproteins, glycolipids, and proteoglycans that are covalently attached to membrane components, forming a carbohydrate-rich coating that can vary in thickness and organization.

In bacteria, the glycocalyx often appears as a capsule or a loose slime layer. The capsule is a well-defined, organized layer that surrounds the cell wall, while the slime layer is more diffuse. These structures can protect bacteria from desiccation, aid in adherence to surfaces, and contribute to virulence by helping evasion of host immune responses.

In animal and other eukaryotic cells, the glycocalyx is a more diffuse, membrane-associated mesh of glycoproteins and glycolipids that extends into the extracellular space. It plays important roles in cell recognition and communication, intercellular adhesion, and protection against mechanical damage. It also participates in signaling pathways and can influence how cells interact with the extracellular matrix and with pathogens.

Physiological and clinical relevance includes the endothelial glycocalyx lining blood vessels, where it contributes to barrier function and mechanotransduction; damage or shedding of this layer is associated with inflammatory states, diabetes, and sepsis. The term derives from Greek roots meaning “sweet cup,” reflecting the sugary coating that covers the cell surface.