enzyme-inhibition
Enzyme inhibition occurs when a molecule binds to an enzyme and blocks its normal catalytic activity, preventing the conversion of substrates into products. In plants, this process is central to regulating essential pathways such as photosynthesis, defense responses, and growth signaling, since naturally occurring or introduced inhibitors can fine-tune metabolic flux at critical control points. Studying enzyme inhibition also helps researchers understand plant resistance to pests, herbicides, and environmental stress, offering insights that can inform crop improvement strategies.
open_in_new WikipediaPubMed · 2026-07-02
Researchers discovered two sulfur-modified versions of a natural plant molecule (inositol thiophosphates) that potently block phytases, the enzymes responsible for breaking down phosphorus stores in seeds, fungi, and mammalian cells. These inhibitors work across kingdoms, hitting phytases in wheat, yeast, and a common mold, and could serve as precise chemical tools for studying how phosphorus is released and recycled in living systems.
IT5 and IT6 inhibit the mammalian phytase MINPP1 with nanomolar IC50 values, meaning they work at concentrations millions of times lower than common inhibitors.
IT6 blocks phytases from wheat, baker's yeast, and Aspergillus niger, demonstrating cross-kingdom inhibitory activity spanning plant, fungal, and mammalian enzymes.
Both IT5 and IT6 resist hydrolysis by MINPP1 while native substrates IP5 and IP6 are readily broken down, confirming they are stable, nonhydrolyzable inhibitors.
