2025.11.25
Research on Importance of high temperature environment to maintain active form of arginine decarboxylase from hyperthermophilic archaeon Pyrobaculum calidifontis. by Prof.Shnsuke Fujiwara is Published in Biochem. Biophys. Res. Commun.
On September 24, 2025, the research paper entitled "Importance of high temperature environment to maintain active form of arginine decarboxylase from hyperthermophilic archaeon Pyrobaculum calidifontis" by Prof Shinsuke Fujiwara and lab members were published in Biochem. Biophys. Res. Commun. The research conducted by Professor Shinsuke Fujiwara’s group demonstrated that thermostable enzymes require high temperatures for proper folding. Pyrobaculum calidifontis is an extreme hyperthermophilic microorganism isolated from volcanic regions in the Philippines, and it can grow even at 100 °C. When the gene encoding this organism’s arginine decarboxylase was introduced and expressed in Escherichia coli, the enzyme formed insoluble aggregates. Because 37 °C—the growth temperature of E. coli—is far too low for the enzyme of a hyperthermophile, it undergoes cold denaturation. The insoluble aggregates were solubilized with guanidine hydrochloride until they became water-soluble, and when they were subjected to a refolding process at the high temperature of 80 °C, the enzyme could be restored to an active molecular form. Arginine decarboxylase is the enzyme responsible for synthesizing agmatine, and it is expected to be useful for agmatine production. Since the solubility of arginine increases at high temperatures, a thermostable enzyme allows the substrate arginine to be supplied at high concentrations, thereby enhancing the productivity of agmatine.
Journal name: Biochem. Biophys. Res. Commun.
Article title: Importance of high temperature environment to maintain active form of arginine decarboxylase from hyperthermophilic archaeon Pyrobaculum calidifontis.
Author(s): Maekawa,K., Fujisaki,D., Ishii,Y., and Fujiwara,S.
