Geranyltransferases

Geranyltransferases are enzymes that catalyze the transfer of a geranyl group, a 10-carbon isoprenoid unit, to a target molecule. This process is known as geranylation and is a crucial step in the biosynthesis of various important natural products. These enzymes are part of the larger family of prenyltransferases, which are responsible for attaching isoprenoid chains to other molecules.

In plants, geranyltransferases play a significant role in the production of secondary metabolites, including essential oils, pigments, and defense compounds. For instance, they are involved in the synthesis of monoterpenes, which contribute to the aroma of many plants. These enzymes also participate in the formation of precursors for other isoprenoid pathways.

The mechanism of geranylation typically involves the transfer of the geranyl pyrophosphate (GPP) substrate to an acceptor molecule, which can be a protein, a nucleotide, or another small molecule. The specificity of a geranyltransferase is determined by its active site, which accommodates both the GPP and the target molecule, facilitating the catalytic reaction.

Research into geranyltransferases is ongoing, with a focus on understanding their diverse roles in different organisms and their potential applications in biotechnology. For example, engineering these enzymes could lead to the production of valuable compounds through metabolic engineering in microorganisms or plants. Their involvement in complex metabolic pathways makes them targets for understanding gene function and biochemical regulation.