Advanced

Influence of water activity on the competition between β-glycosidase-catalysed transglycosylation and hydrolysis in aqueous hexanol

Hansson, Therese LU ; Andersson, Mats LU ; Wehtje, Ernst LU and Adlercreutz, Patrick LU (2001) In Enzyme and Microbial Technology 29(8-9). p.527-534
Abstract

Five different β-glycosidases (Pyrococcus furiosus β-glucosidase, Sulfolobus solfataricus β-galactosidase, Caldocellum saccharolyticum β-glucosidase, almond β-glucosidase and Escherichia coli β-galactosidase) were evaluated as transglycosylation catalysts in hexanol containing various amounts of water. All enzymes catalysed both hydrolysis and transglycosylation of the glycosidic substrates (pentyl- and p-nitrophenyl-β-glucoside and p-nitrophenyl-β-galactoside). From the concentration ratio (alcohol/water) it was expected that the transglycosylation/hydrolysis ratio would decrease with increasing water activity in the hexanol. However, for all enzymes tested the selectivity for the alcohol increased with increasing water activity. This... (More)

Five different β-glycosidases (Pyrococcus furiosus β-glucosidase, Sulfolobus solfataricus β-galactosidase, Caldocellum saccharolyticum β-glucosidase, almond β-glucosidase and Escherichia coli β-galactosidase) were evaluated as transglycosylation catalysts in hexanol containing various amounts of water. All enzymes catalysed both hydrolysis and transglycosylation of the glycosidic substrates (pentyl- and p-nitrophenyl-β-glucoside and p-nitrophenyl-β-galactoside). From the concentration ratio (alcohol/water) it was expected that the transglycosylation/hydrolysis ratio would decrease with increasing water activity in the hexanol. However, for all enzymes tested the selectivity for the alcohol increased with increasing water activity. This counteracted the effect of higher water concentration and in most cases the transglycosylation/hydrolysis ratio increased with increasing water activity. On the other hand, in hexanol/water two-phase systems, hydrolysis was by far the dominating reaction even though the total activity increased for all enzymes. The selectivity values were used to predict the maximal reaction yields in the kinetically controlled reactions. However, deviations were found in cases when the reactions became thermodynamically controlled: at high water contents secondary hydrolysis reduced the transglycosylation yields while higher transglycosylation yields than predicted were obtained at low water activity in some cases using enzymes poorly selective for the alcohol.

(Less)
Please use this url to cite or link to this publication:
author
; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Hexanol, Hydrolysis, Selectivity, Transglycosylation, Water activity, β-glycosidase
in
Enzyme and Microbial Technology
volume
29
issue
8-9
pages
8 pages
publisher
Elsevier
external identifiers
  • scopus:0035813475
ISSN
0141-0229
DOI
10.1016/S0141-0229(01)00421-5
language
English
LU publication?
yes
id
dab279c4-23c9-4f4e-b750-5f9508ef837a
date added to LUP
2019-06-20 15:17:17
date last changed
2020-09-30 06:15:25
@article{dab279c4-23c9-4f4e-b750-5f9508ef837a,
  abstract     = {<p>Five different β-glycosidases (Pyrococcus furiosus β-glucosidase, Sulfolobus solfataricus β-galactosidase, Caldocellum saccharolyticum β-glucosidase, almond β-glucosidase and Escherichia coli β-galactosidase) were evaluated as transglycosylation catalysts in hexanol containing various amounts of water. All enzymes catalysed both hydrolysis and transglycosylation of the glycosidic substrates (pentyl- and p-nitrophenyl-β-glucoside and p-nitrophenyl-β-galactoside). From the concentration ratio (alcohol/water) it was expected that the transglycosylation/hydrolysis ratio would decrease with increasing water activity in the hexanol. However, for all enzymes tested the selectivity for the alcohol increased with increasing water activity. This counteracted the effect of higher water concentration and in most cases the transglycosylation/hydrolysis ratio increased with increasing water activity. On the other hand, in hexanol/water two-phase systems, hydrolysis was by far the dominating reaction even though the total activity increased for all enzymes. The selectivity values were used to predict the maximal reaction yields in the kinetically controlled reactions. However, deviations were found in cases when the reactions became thermodynamically controlled: at high water contents secondary hydrolysis reduced the transglycosylation yields while higher transglycosylation yields than predicted were obtained at low water activity in some cases using enzymes poorly selective for the alcohol.</p>},
  author       = {Hansson, Therese and Andersson, Mats and Wehtje, Ernst and Adlercreutz, Patrick},
  issn         = {0141-0229},
  language     = {eng},
  month        = {11},
  number       = {8-9},
  pages        = {527--534},
  publisher    = {Elsevier},
  series       = {Enzyme and Microbial Technology},
  title        = {Influence of water activity on the competition between β-glycosidase-catalysed transglycosylation and hydrolysis in aqueous hexanol},
  url          = {http://dx.doi.org/10.1016/S0141-0229(01)00421-5},
  doi          = {10.1016/S0141-0229(01)00421-5},
  volume       = {29},
  year         = {2001},
}