Effects of arachidonic acid concentration on prostaglandin biosynthesis and feasibility of semibatch processes.
The reaction characteristics of prostaglandin E2 biosynthesis by PGH-synthase and PGE2 isomerase and the substrate dependency of this biosynthesis were studied. The activity of PG-synthases was blocked by the inhibitory action of one or more byproducts, probably resulting from the action of PGH-synthase. This inhibitory action then appeared to be partly reversible, indicating that the substrate and the inhibitor compete for the catalytic sites. According to these findings, the feasibility of a successful semibatch biosynthesis was investigated. A combination of the substrate concentration reducing procedure and the semibatch process resulted in an about 3.5-fold higher increase in the total amount of PGE2 formed in comparison with the batch results obtained at the substrate concentration of 1.0 mg/cm3. Since the cost of enzyme is a governing factor in this biosynthesis, development of semibatch biosynthesis of PGE2 becomes a matter of economic importance.
Sada
E
E
Department of Chemical Engineering, Kyoto University, Japan.
Katoh
S
S
Kheirolomoom
A
A
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D016861:Cyclooxygenase Inhibitors; D015232:Dinoprostone / Q000096:biosynthesis*; D066298:In Vitro Techniques; D019746:Intramolecular Oxidoreductases; D007535:Isomerases / Q000378:metabolism; D007700:Kinetics; D008081:Liposomes; D008297:Male; D008861:Microsomes / Q000378:metabolism; D000071876:Prostaglandin-E Synthases; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D012669:Seminal Vesicles / Q000378:metabolism; D012756:Sheep
D001095:Arachidonic Acids; D016861:Cyclooxygenase Inhibitors; D008081:Liposomes; D016718:Arachidonic Acid; D011451:Prostaglandin-Endoperoxide Synthases; D007535:Isomerases; D019746:Intramolecular Oxidoreductases; D000071876:Prostaglandin-E Synthases; D015232:Dinoprostone