title: Crosslinked enzyme aggregates in hierarchically-ordered mesoporous silica: a simple and effective method for enzyme stabilization.
abstract: alpha-chymotrypsin (CT) and lipase (LP) were immobilized in hierarchically-ordered mesocellular mesoporous silica (HMMS) in a simple but effective way for the enzyme stabilization, which was achieved by the enzyme adsorption followed by glutaraldehyde (GA) crosslinking. This resulted in the formation of nanometer scale crosslinked enzyme aggregates (CLEAs) entrapped in the mesocellular pores of HMMS (37 nm), which did not leach out of HMMS through narrow mesoporous channels (13 nm). CLEA of alpha-chymotrypsin (CLEA-CT) in HMMS showed a high enzyme loading capacity and significantly increased enzyme stability. No activity decrease of CLEA-CT was observed for 2 weeks under even rigorously shaking condition, while adsorbed CT in HMMS and free CT showed a rapid inactivation due to the enzyme leaching and presumably autolysis, respectively. With the CLEA-CT in HMMS, however, there was no tryptic digestion observed suggesting that the CLEA-CT is not susceptible to autolysis. Moreover, CLEA of lipase (CLEA-LP) in HMMS retained 30% specific activity of free lipase with greatly enhanced stability. This work demonstrates that HMMS can be efficiently employed as host materials for enzyme immobilization leading to highly enhanced stability of the immobilized enzymes with high enzyme loading and activity.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors.forename: Moon Il
authors.initials: MI
authors.lastname: Kim
authors.forename: Jungbae
authors.initials: J
authors.lastname: Kim
authors.forename: Jinwoo
authors.initials: J
authors.lastname: Lee
authors.forename: Hongfei
authors.initials: H
authors.lastname: Jia
authors.forename: Hyon Bin
authors.initials: HB
authors.lastname: Na
authors.forename: Jong Kyu
authors.initials: JK
authors.lastname: Youn
authors.forename: Ja Hun
authors.initials: JH
authors.lastname: Kwak
authors.forename: Alice
authors.initials: A
authors.lastname: Dohnalkova
authors.forename: Jay W
authors.initials: JW
authors.lastname: Grate
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.forename: Taeghwan
authors.initials: T
authors.lastname: Hyeon
authors.forename: Hyun Gyu
authors.initials: HG
authors.lastname: Park
authors.forename: Ho Nam
authors.initials: HN
authors.lastname: Chang
mesh_terms: D002918:Chymotrypsin / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry*; D008049:Lipase / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D008954:Models, Biological; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D003432:Cross-Linking Reagents; D004800:Enzymes, Immobilized; D012822:Silicon Dioxide; D008049:Lipase; D002918:Chymotrypsin; C117608:alpha-chymotrypsin