Insect chitin synthase (CHS (sometimes further specified as CHS1 or CHS2 in literature))

Insect chitin synthase is a membrane-integral enzyme classified as a glycosyltransferase (family 2, EC 2.4.1.16) that catalyzes the polymerization of UDP-N-acetylglucosamine into chitin, a key structural polysaccharide in insects[1][2][3][4]. Chitin forms the scaffold of the exoskeleton (cuticle), peritrophic matrix in the gut, and tracheal linings, supporting growth, morphogenesis, and protection against environmental harm[2][4][5]. Insect genomes typically encode two primary chitin synthase isoforms: CHS1 (predominantly involved in cuticle formation) and CHS2 (involved in midgut/peritrophic matrix synthesis)[2]. The enzyme is the terminal step in the chitin biosynthetic pathway, requiring UDP-N-acetylglucosamine and divalent cations as cofactors, and operates at the plasma membrane where it synthesizes and extrudes chitin polymers into the extracellular space[1][3]. Insect chitin synthase has become an important molecular target in pesticide and insecticide development; its inhibition results in catastrophic defects in cuticle integrity and larval development, making it a selective target for disrupting insect pests and vectors[3]. Various small molecule inhibitors, including nikkomycin Z and polyoxin D, bind either to the substrate or product-binding sites, blocking enzyme function and leading to insect death, with promising applications in crop protection and disease vector control[3].

Other names

Chitin synthaseCHSchitin synthetaseCHS1 (cuticular form)CHS2 (gut/peritrophic matrix form)EC 2.4.1.16

Competitive inhibition of UDP-N-acetylglucosamine binding (e.g., nikkomycin Z, polyoxin D)\nEnzyme inactivation/functional disruption leading to failed chitin polymerization and defects in cuticle/gut structure