Proteoglycans are heavily glycosylated proteins. These proteoglycans are present in the extracellular matrix of the animal cells and acts as a lubricant for the cells.
Proteoglycans are proteins that are covalently bonded with muco polysaccharidse. Proteoglycans are formed by the bonding between proteins and carbohydrates ( polysaccharides). Proteoglycans can combine with collagen to form cartilage and may affect the stability of a protein.
They cause DNA to replicate. They denature each other. They are molecules made of amino acids that speed up chemical reactions by lowering the activation energy.