Linked Life Data

21552271

Source:http://linkedlifedata.com/resource/pubmed/id/21552271

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2011-5-18
pubmed:abstractText
? exonuclease degrades one strand of duplex DNA in the 5'-to-3' direction to generate a 3' overhang required for recombination. Its ability to hydrolyze thousands of nucleotides processively is attributed to its ring structure, and most studies have focused on the processive phase. Here we have used single-molecule fluorescence resonance energy transfer (FRET) to reveal three phases of ? exonuclease reactions: the initiation, distributive and processive phases. The distributive phase comprises early reactions in which the 3' overhang is too short to stably engage with the enzyme. A mismatched base is digested one-fifth as quickly as a Watson-Crick-paired base, and multiple concatenated mismatches have a cooperatively negative effect, highlighting the crucial role of base pairing in aligning the 5' end toward the active site. The rate-limiting step during processive degradation seems to be the post-cleavage melting of the terminal base pair. We also found that an escape from a known pausing sequence requires enzyme backtracking.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1552-4469
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
367-74
pubmed:dateRevised
2011-9-26
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Single-molecule analysis reveals three phases of DNA degradation by an exonuclease.
pubmed:affiliation
Department of Physics and the Center for the Physics of Living Cells, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural