Abstract:
:The characteristics of horseradish peroxidase (HRP) immobilized onto Sepharose by a photochemical-initiated graft copolymerization are presented. Active copolymers were synthesized using different amounts of glycidylmethacrylate (GMA), bisacryloylpiperazine (BAP), or 1,3,5-hexhydrotriacryloyl-(s)-triazine (HTsT) as functional monomer. The activities, the K'(m) values (pGMA) copolymers: 0.53-0.76 x 10(-4)M; pBAP copolymers: 0.90-1.4 x 10(-4); pHTsT copolymers: 1.8-2.6 x 10(-4)M and the thermal stabilities of the enzyme copolymers were strictly connected to the type of polymer. By varying the polymer amount present in a given copolymer, significant differences were found in the thermostability properties of pBAP and pHTsT copolymers both when checked in water or in phosphate buffer. No differences were found for pGMA copolymers. The samples in which there are the lowest pBAP or pHTsT content resulted the most stable. The activity retained after 240 min at 60 degrees C by free HRP and pGMA-HRP was 30% whereas by pBAP-HRP and pHTsT-HRP it was 50 and 75% of the original. Operational stability of the materials was in agreement with thermostability data. These results are discussed in terms of enzyme microenvironment which is strongly affected by the different network of the three polymers.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Cremonesi P,D'Angiuro Ldoi
10.1002/bit.260250310subject
Has Abstractpub_date
1983-03-01 00:00:00pages
735-44issue
3eissn
0006-3592issn
1097-0290journal_volume
25pub_type
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journal_title:Biotechnology and bioengineering
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