Linked Life Data

9765249

Source:http://linkedlifedata.com/resource/pubmed/id/9765249

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
42
pubmed:dateCreated
1998-11-6
pubmed:abstractText
The effect of DNA secondary structure on polymerization catalyzed by human immunodeficiency virus (HIV-1) reverse transcriptase (RT) was studied using a synthetic 66-nucleotide DNA template containing a stable hairpin structure. Four RT pause sites were identified within the first half of the hairpin stem. Additionally, five weak pause sites within the second half of the stem and the loop of the hairpin were identified at low temperatures. These weak pause sites were relocated to the site of the first few stem base pairs of two new hairpins formed due to a change in DNA secondary structure. Each pause site was correlated with a high free energy barrier of melting the stem base pair. Pre-steady state kinetic analysis of single nucleotide incorporation showed that polymerization at each pause site occurred by both a fast phase (10-20 s-1) and a slow phase (0. 02-0.07 s-1) during a single binding event. The reaction amplitudes of the fast phase were small (4-10% of enzyme sites), whereas the amplitudes of the slow phase were large (14-40%) at the pause sites. In contrast, only a single phase with a large reaction amplitude (32-50%) and a fast nucleotide incorporation rate (33-87 s-1) was observed at the non-pause sites. DNA substrates at all sites had similar dissociation rates (0.14-0.29 s-1) and overall binding affinity (16-86 nM). These results suggest that the DNA substrates at pause sites were bound in both productive and non-productive states at the polymerase site of RT. The non-productively bound DNA was slowly converted into a productive state upon melting of the next stem base pair without dissociation of the DNA from RT.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
273
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27259-67
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
DNA secondary structure effects on DNA synthesis catalyzed by HIV-1 reverse transcriptase.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, the Pennsylvania State University, University Park, Pennsylvania 16802, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.