Linked Life Data

8955090

Source:http://linkedlifedata.com/resource/pubmed/id/8955090

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
51
pubmed:dateCreated
1997-1-23
pubmed:abstractText
The replication of the hepatitis B viral DNA genome proceeds through a pregenomic RNA intermediate. This pregenomic RNA subsequently serves as the template for the formation of the viral DNA by the reverse transcriptase activity of the viral P gene product. The P gene product is believed to be a multifunctional enzyme with DNA-dependent DNA polymerase, RNA-dependent DNA polymerase, and RNase H activities. Detailed biochemical studies of this protein have not been performed because of the inability to obtain sufficient amounts of the enzyme from the virus and by the inability to produce the enzyme in heterologous expression systems. The RNase H activity is essential for viral replication and is believed to be responsible for the degradation of the RNA pregenomic intermediate as well as for generating the short RNA primer that is required for DNA second strand synthesis. We have assembled an expression vector which directs the synthesis of a protein that corresponds to the putative RNase H domain of the P gene product and having a carboxyl-terminal polyhistidine tag to facilitate purification. The protein has been expressed in Escherichia coli and purified to yield 1-2 mg of protein/liter of culture. This protein has RNase H activity as defined by its ability to degrade the RNA component of RNA-DNA hybrids but not the DNA component. The RNase H has a basic optimum pH, is active only in the presence of reducing agents, and is dependent on the presence of divalent cations, with magnesium being preferred over manganese.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
32617-22
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Expression, purification, and characterization of an active RNase H domain of the hepatitis B viral polymerase.
pubmed:affiliation
Department of Biochemistry and Molecular Biophysics, Virginia Commonwealth University, Richmond, Virginia 23298-0614, USA.
pubmed:publicationType
Journal Article