The role of enzyme adsorption in the enzymatic degradation of an aliphatic polyester.
adsorption kinetics
enzymatic degradation
mutagenesis
polyhydroxyalkanoates
surface need
Journal
Enzyme and microbial technology
ISSN: 1879-0909
Titre abrégé: Enzyme Microb Technol
Pays: United States
ID NLM: 8003761
Informations de publication
Date de publication:
Jan 2019
Jan 2019
Historique:
received:
23
04
2018
revised:
10
10
2018
accepted:
12
10
2018
entrez:
7
11
2018
pubmed:
7
11
2018
medline:
23
2
2019
Statut:
ppublish
Résumé
The enzyme catalyzed degradation of poly(3-hydroxybutyrate) (PHB) is a two-step process consisting of the adsorption of the enzyme on the surface of a PHB substrate and the cleavage of ester bonds. A deactivated enzyme was prepared by point mutagenesis to separate the two steps from each other. Measurements carried out with active and inactive enzymes on PHB particles proved that mutagenesis was successful and the modified enzyme did not catalyze degradation. Based on the Michaelis-Menten approach a kinetic model was proposed which could describe the processes quantitatively, the agreement between prediction and the measured data was excellent. The separation of the two processes allowed the determination of the adsorption kinetics of the enzyme; the rate constants of the adsorption and desorption process were determined for the first time. Comparison of these constants to reaction rates showed that adsorption is not instantaneous and can be the rate-determining step. The area occupied by an enzyme molecule was also determined (13.1 nm
Identifiants
pubmed: 30396391
pii: S0141-0229(18)30232-1
doi: 10.1016/j.enzmictec.2018.10.005
pii:
doi:
Substances chimiques
Hydroxybutyrates
0
Polyesters
0
poly-beta-hydroxybutyrate
26063-00-3
Carboxylic Ester Hydrolases
EC 3.1.1.-
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
110-116Informations de copyright
Copyright © 2018 Elsevier Inc. All rights reserved.