Thioesteritaasit

Thioesteritaasit, known in English as thioesterases, are enzymes that catalyze the hydrolysis of thioester bonds, converting thioesters into their corresponding acids and thiols. These enzymes play a crucial role in cellular metabolism by regulating the concentrations of thioester intermediates, which are common in fatty acid synthesis, polyketide production, and various protein modification pathways. Thioesterases can be classified into several families based on structural motifs and substrate preferences, including the hotdog-fold thioesterases, the GDSL lipase family, and the AB hydrolase fold thioesterases.

In metabolic pathways, thioesterases help terminate chain elongation reactions by cleaving the thioester linkages formed at the active sites of polyketide synthases and fatty acid synthases. They also participate in the removal of toxic intermediates, such as S‑deacetylation of coenzyme A derivatives. Additionally, thioesterases are involved in the post‑translational modification of proteins, where they remove acyl groups from lysine residues, thereby modulating protein function and signaling pathways.

Industrial applications of thioesterases include their use as biocatalysts for the synthesis of fine chemicals, biodiesel production by manipulating fatty acid chain lengths, and the engineering of synthetic metabolic pathways for novel compound biosynthesis. Research continues to uncover new thioesterase family members with unique specificities, offering potential for biotechnology and pharmaceutical development.