Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2011-2-23
pubmed:abstractText
The cytosolic sulfotransferase hSULT2A1 is the major hydroxysteroid (alcohol) sulfotransferase in human liver, and it catalyzes the 3'-phosphoadenosine-5'-phosphosulfate (PAPS)-dependent sulfation of various endogenous hydroxysteroids as well as many xenobiotics that contain alcohol and phenol functional groups. The hSULT2A1 often displays substrate inhibition, and we have hypothesized that a key element in this response to increasing substrate concentration is the formation of non-productive ternary dead-end enzyme complexes involving the nucleotide product, adenosine 3',5'-diphosphate (PAP). One of these substrates for hSULT2A1 is dehydroepiandrosterone (DHEA), a major circulating steroid hormone in humans that serves as precursor to both androgens and estrogens. We have utilized DHEA in both initial velocity studies and equilibrium binding experiments in order to evaluate the potential role of ternary complexes in substrate inhibition of the enzyme. Our results indicate that hSULT2A1 forms non-productive ternary complexes that involve either DHEA or dehydroepiandrosterone sulfate, and the formation of these ternary complexes displays negative cooperativity in the binding of DHEA.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1096-0384
pubmed:author
pubmed:copyrightInfo
Copyright © 2010 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
507
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
232-40
pubmed:dateRevised
2011-5-16
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Substrate inhibition in human hydroxysteroid sulfotransferase SULT2A1: studies on the formation of catalytically non-productive enzyme complexes.
pubmed:affiliation
Division of Medicinal and Natural Products Chemistry, College of Pharmacy, The University of Iowa, Iowa City, IA 52242, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural