Plants manufacture compounds to help them repel pests, attract pollinators,
cure infections and protect themselves from excess temperatures, drouht, and
other hazards in the environment. Salk Institute researchers who are
studying how plants evolved the abilities to make these natural chemicals
have now uncovered how an enzyme called chalcone isomerase evolved to enable
plants to make products that are important to their survival. The
researchers hope that this knowledge facilitates the manufacturing of
products that are beneficial to humans, including medications and improved
crops.

Chalcone isomerase acts as a catalyst to accelerate plant chemical
reactions. It also helps ensure that chemicals made in the plant are in
proper form since molecules with the same chemical formula can take two
different variations that are mirror images of each other (called isomers).
The researchers identified the part of chalcone isomerase's structure that
allowed it to catalyze reactions incredibly fast while also ensuring it
makes the proper, biologically active isomer. These reactions lead to a host
of activities in plants, including converting primary metabolites like
phenylalanine and tyrosine into vital specialized molecules called
flavonoids.

The researchers found that the amino acid arginine, one of many amino acids
linked together in chalcone isomerase sat in a location, shaped by
evolution, that allowed it to play the key role in how chalcone isomerase
reactions were catalyzed. The researchers said that their new understanding
of chalcone isomerase enables them to design molecular systems that can
carry out a particular task even in the next generation of nutritionally
dense crops capable of transforming the greenhouse gas carbon dioxide into
molecules essential for life.

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elopment-of-medicines-and-other-products/