Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-12-6
pubmed:abstractText
The employment of enzymes as catalysts within organic media has traditionally been hampered by the reduced enzymatic activities when compared to catalysis in aqueous solution. Although several complementary hypotheses have provided mechanistic insights into the causes of diminished activity, further development of biocatalysts would greatly benefit from effective chemical strategies (e.g., PEGylation) to ameliorate this event. Herein we explore the effects of altering the solvent composition from aqueous buffer to 1,4-dioxane on structural, dynamical, and catalytic properties of the model enzyme subtilisin Carlsberg (SBc). Furthermore, we also investigate the effects of dissolving the enzyme in 1,4-dioxane through chemical modification with poly(ethylene)-glycol (PEG, M(W) = 20 kDa) on these enzyme properties. In 1,4-dioxane a 10(4)-fold decrease in the enzyme's catalytic activity was observed for the hydrolysis reaction of vinyl butyrate with D(2)O and a 50% decrease in enzyme structural dynamics as evidenced by reduced amide H/D exchange kinetics occurred. Attaching increasing amounts of PEG to the enzyme reversed some of the activity loss. Evaluation of the structural dynamic behavior of the PEGylated enzyme within the organic solvent revealed an increase in structural dynamics at increased PEGylation. Correlation analysis between the catalytic and structural dynamic parameters revealed that the enzyme's catalytic activity and enantioselectivity depended on the changes in protein structural dynamics within 1,4-dioxane. These results demonstrate the importance of protein structural dynamics towards regulating the catalytic behavior of enzymes within organic media.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1097-0290
pubmed:author
pubmed:copyrightInfo
(c) 2007 Wiley Periodicals, Inc.
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
99
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9-17
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Effect of PEG modification on subtilisin Carlsberg activity, enantioselectivity, and structural dynamics in 1,4-dioxane.
pubmed:affiliation
Department of Chemistry, University of Puerto Rico, Río Piedras Campus, P.O. Box 23346, San Juan 00931-3346, Puerto Rico.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural