Linked Life Data

16837570

Source:http://linkedlifedata.com/resource/pubmed/id/16837570

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2006-9-21
pubmed:abstractText
Hydrolase activity from human liver and small intestine microsomes was compared with that of recombinant human carboxylesterases, hCE-1 and hCE-2. Although both hCE-1 and hCE-2 are present in human liver, the dominant component was found to be hCE-1, whereas the hydrolase activity of the human small intestine was found to be predominantly hCE-2. hCE-2 has a limited ability to hydrolyze large acyl compound substrates. Interestingly, propranolol derivatives, good substrates for hCE-2, were easily hydrolyzed by substitution of the methyl group on the 2-position of the acyl moiety, but were barely hydrolyzed when the methyl group was substituted on the 3-position. These findings suggest that hCE-2 does not easily form acylated intermediates because of conformational interference in its active site. In contrast, hCE-1 could hydrolyze a variety of substrates. The hydrolytic activity of hCE-2 increased with increasing alcohol chain length in benzoic acid derivative substrates, whereas hCE-1 preferentially catalyzed the hydrolysis of substrates with short alcohol chains. Kinetic data showed that the determining factor for the rate of hydrolysis of p-aminobenzoic acid esters was V(max) for hCE-1 and K(m) for hCE-2. Furthermore, the addition of hydrophobic alcohols to the reaction mixture with p-aminobenzoic acid propyl ester induced high and low levels of transesterification by hCE-1 and hCE-2, respectively. When considering the substrate specificities of hCE-1, it is necessary to consider the transesterification ability of hCE-1, in addition to the binding structure of the substrate in the active site of the enzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0090-9556
pubmed:author
pubmed:issnType
Print
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1734-41
pubmed:dateRevised
2010-5-20
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Substrate specificity of carboxylesterase isozymes and their contribution to hydrolase activity in human liver and small intestine.
pubmed:affiliation
Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-Honmachi, Kumamoto 862-0973, Japan. iteruko@gpo.kumamoto-u.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't