Linked Life Data

15831490

Source:http://linkedlifedata.com/resource/pubmed/id/15831490

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
25
pubmed:dateCreated
2005-6-20
pubmed:abstractText
In its x-ray crystal structures, alpha-1,4-N-acteylhexosaminyltransferase (exostosin-like protein 2 (EXTL2)) forms no direct interaction with the N-acetyl group of the UDP-N-acetylhexosamine. Mutation of the residues that interact with the hydroxyl groups of the donor not only failed to abrogate donor binding but in fact increased binding affinity. Isothermal titration calorimetry is now used to examine the binding nature of various UDP-sugars in H2O and D2O solutions. UDP-N-acetylhexosamines bind to EXTL2 with a high affinity in both solutions, resulting in a relatively large increase of entropy, whereas the weak binding of UDP-galactose and -glucose, which occurred only in D2O solution, only slightly increased entropy. Thus, specific donor binding appears to undergo two distinct steps, beginning with the N-acetyl group expelling water from the donor. enzyme complex into the bulk solvent followed by positioning of the donor into the binding site for the subsequent interactions with the enzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
280
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
23441-5
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Two-step mechanism that determines the donor binding specificity of human UDP-N-acetylhexosaminyltransferase.
pubmed:affiliation
Pharmacogenetic Section, Laboratory of Reproductive and Developmental Toxicology, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
pubmed:publicationType
Journal Article