Linked Life Data

8662636

Source:http://linkedlifedata.com/resource/pubmed/id/8662636

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1996-8-29
pubmed:abstractText
D1R1-545, an active subdomain of the large subunit of vaccinia virus mRNA capping enzyme possessing ATPase, RNA 5'-triphosphatase, and guanylyltransferase activities, was expressed in Escherichia coli and shown to be functionally equivalent to the heterodimeric enzyme (Myette, J. R., and Niles, E. G. (1996) J. Biol. Chem. 271, 11936-11944). A detailed characterization of the phosphohydrolytic activities of D1R1-545 demonstrates that, in addition to ATPase and RNA 5'-triphosphatase activities, the capping enzyme also possesses a general nucleoside triphosphate phosphohydrolase activity that lacks a preference for the nucleoside base or sugar. Nucleoside triphosphate and mRNA saturation kinetics are markedly different, with RNA exhibiting a Km and turnover number 100- and 10-fold less, respectively, than those values measured for any NTP. The linear competitive inhibition of RNA 5'-triphosphatase activity by ATP, and the relative manner by which both ATPase and RNA 5'-triphosphatase activities are inhibited by specific oligonucleotides, kinetically demonstrate that each activity is carried out at a common active site. Direct UV photo-cross-linking of either 32P-radiolabeled ATP or 23-mer triphosphorylated RNA, followed by cyanogen bromide cleavage of the photo-linked enzyme, localizes the major binding site for both ATP and RNA to a region between amino acids 1 and 221. The inability of ATP to competitively inhibit either E approximately GMP formation or the transfer of GMP to RNA kinetically differentiates the phosphohydrolase active site from the guanylyltransferase active site.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
271
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11945-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Characterization of the vaccinia virus RNA 5'-triphosphatase and nucleotide triphosphate phosphohydrolase activities. Demonstrate that both activities are carried out at the same active site.
pubmed:affiliation
Department of Biochemistry, State University of New York, School of Medicine and Biomedical Sciences, Buffalo 14214, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.