Linked Life Data

9268340

Source:http://linkedlifedata.com/resource/pubmed/id/9268340

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
35
pubmed:dateCreated
1997-10-2
pubmed:abstractText
To understand how ribonucleases H recognize RNA-DNA hybrid substrates, we analyzed kinetic parameters of binding of Escherichia coli RNase HI to RNA-DNA hybrids ranging in length from 18 to 36 base pairs (bp) using surface plasmon resonance (BIAcoreTM). The kon and koff values for the binding of the enzyme to the 36-bp substrate were 1.5 x 10(6) M-1 s-1 and 3.2 x 10(-2) s-1, respectively. Similar values were obtained with the shorter substrates. Using uncleavable 2'-O-methylated RNA-DNA substrates, values for kon and koff were 2.1 x 10(5) M-1 s-1 and 1.3 x 10(-1) s-1 in the absence of Mg2+ that were further reduced in the presence of Mg2+ to 7.4 x 10(3) M-1 s-1 and 2.6 x 10(-2) s-1. Kinetic parameters similar to the wild-type enzyme were obtained using an active-site mutant enzyme, Asp134 replaced by Ala, whereas a greatly reduced on-rate was observed for another inactive mutant enzyme, in which the basic protrusion is eliminated, thereby distinguishing between poor catalysis and inability to bind to the substrate. Stoichiometric analyses of RNase HI binding to substrates of 18, 24, 30, and 36 bp are consistent with previous reports suggesting that RNase HI binds to 9-10 bp of RNA-DNA hybrid.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
22015-22
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Kinetic and stoichiometric analysis for the binding of Escherichia coli ribonuclease HI to RNA-DNA hybrids using surface plasmon resonance.
pubmed:affiliation
Department of Material and Life Sciences, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565, Japan.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.