Chitin crustacean waste and mushrooms for possible development of products in tissue engineering, medicine, and industry. Chitin Chitin (CHON) ( ), a long-chain polymer of "N"-acetylglucosamine, is a derivative of glucose. It is a primary component of cell walls in fungi, the exoskeletons of arthropods, such as crustaceans (e.g., crabs, lobsters and shrimps) and insects, the radulae of molluscs, cephalopod beaks, and the scales of fish and lissamphibians. The structure of chitin is comparable to another polysaccharide - cellulose, forming crystalline nanofibrils or whiskers. In terms of function, it may be compared to the protein keratin. Chitin has proved useful for
UTP—glucose-1-phosphate uridylyltransferase including the liver and the muscles. An exception is the brain, which has high levels of glycogen but low specific activity of UTP—glucose-1-phosphate uridylyltransferase. In animal cells, UTP—glucose-1-phosphate uridylyltransferase is found predominantly in the cytoplasm. UTP—glucose-1-phosphate uridylyltransferase is also required for galactose metabolism in animals and microorganisms. In galactose metabolism, the enzyme galactose 1-phosphate uridylyltransferase transfers a phosphate from UDP-glucose to galactose 1-phosphate to produce UDP-galactose, which is then converted to UDP-glucose. Bacteria with defective UTP—glucose-1-phosphate uridylyltransferase are unable to incorporate galactose into their cell walls. In this enzyme’s primary reaction, the phosphate group on glucose-1-phosphate replaces the phosphoanhydride bond