title: Stabilization of Phenylalanine Ammonia Lyase from Rhodotorula glutinis by Encapsulation in Polyethyleneimine-Mediated Biomimetic Silica.
abstract: Phenylalanine ammonia lyase (PAL) from Rhodotorula glutinis was encapsulated within polyethyleneimine-mediated biomimetic silica. The main factors in the preparation of biomimetic silica were optimized by response surface methodology (RSM). Compared to free PAL (about 2 U), the encapsulated PAL retained more than 43 % of their initial activity after 1 h of incubation time at 60 °C, whereas free PAL lost most of activity in the same conditions. It was clearly indicated that the thermal stability of PAL was improved by encapsulation. Moreover, the encapsulated PAL exhibited the excellent stability of the enzyme against denaturants and storage stability, and pH stability was improved by encapsulation. Operational stability of 7 reaction cycles showed that the encapsulated PAL was stable. Nevertheless, the K m value of encapsulated PAL in biomimetic silica was higher than that of the free PAL due to lower total surface area and increased mass transfer resistance.
authors.affiliation: Research Center for Fermentation Engineering of Hebei, College of Bioscience and Bioengineering, Hebei University of Science and Technology, 70 Yuhua East Road, Shijiazhang, 050018, People's Republic of China, cjd007cn@163.com.
authors.forename: Jiandong
authors.initials: J
authors.lastname: Cui
authors.forename: Longhao
authors.initials: L
authors.lastname: Liang
authors.forename: Cong
authors.initials: C
authors.lastname: Han
authors.forename: Rong
authors.initials: R
authors.lastname: Lin Liu
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D040761:Biomimetic Materials / Q000737:chemistry*; D003470:Culture Media / Q000737:chemistry; D004339:Drug Compounding / Q000379:methods; D057075:Enzyme Assays; D004795:Enzyme Stability; D017743:Equipment Reuse; D005163:Factor Analysis, Statistical; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010650:Phenylalanine Ammonia-Lyase / Q000737:chemistry* / Q000302:isolation & purification; D011094:Polyethyleneimine / Q000737:chemistry*; D012248:Rhodotorula / Q000737:chemistry / Q000201:enzymology* / Q000254:growth & development; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D012822:Silicon Dioxide; D011094:Polyethyleneimine; D010650:Phenylalanine Ammonia-Lyase