Linked Life Data

20348261

Source:http://linkedlifedata.com/resource/pubmed/id/20348261

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2010-5-12
pubmed:abstractText
Primase, encoded by dnaG in bacteria, is a specialized DNA-dependent RNA polymerase that synthesizes RNA primers de novo for elongation by DNA polymerase. Genome sequence analysis has revealed two distantly related dnaG genes, TtdnaG and TtdnaG(2), in the thermophilic bacterium Thermoanaerobacter tengcongensis. Both TtDnaG (600 amino acids) and TtDnaG2 (358 amino acids) exhibit primase activities in vitro at a wide range of temperatures. Interestingly, the template recognition specificities of these two primases are quite distinctive. When trinucleotide-specific templates were tested, TtDnaG initiated RNA primer synthesis efficiently only on templates containing the trinucleotide 5'-CCC-3', not on the other 63 possible trinucleotides. When the 5'-CCC-3' sequence was flanked by additional cytosines or guanines, the initiation efficiency of TtDnaG increased remarkably. Significantly, TtDnaG could specifically and efficiently initiate RNA primer synthesis on a limited set of tetranucleotides composed entirely of cytosines and guanines, indicating that TtDnaG initiated RNA primer synthesis more preferably on GC-containing tetranucleotides. In contrast, it seemed that TtDnaG2 had no specific initiation nucleotides, as it could efficiently initiate RNA primer synthesis on all templates tested. The DNA binding affinity of TtDnaG2 was usually 10-fold higher than that of TtDnaG, which might correlate with its high activity but low template specificity. These distinct priming activities and specificities of TtDnaG and TtDnaG2 might shed new light on the diversity in the structure and function of the primases.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1098-5530
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
192
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2670-81
pubmed:dateRevised
2011-3-3
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Two distantly homologous DnaG primases from Thermoanaerobacter tengcongensis exhibit distinct initiation specificities and priming activities.
pubmed:affiliation
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 Beichen West Road, Chaoyang District, Beijing 100101, People's Republic of China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't