Linked Life Data

168948

Source:http://linkedlifedata.com/resource/pubmed/id/168948

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1975-11-25
pubmed:abstractText
Snake venom phosphodiesterase liberates the O2-methylnucleoside (Nm) constituents of RNA as the corresponding 5-nucleotides (PNm), which, in contrast to normal 5-nucleotides (pN), are resistant to dephosphorylation by venom 5-nucleotidase. This property provides the basis of a convenient and highly reproducible quantitative assay for Nm residues in RNA. The assay method involves: (1) hydrolysis of RNA with whole or partially-purified snake venom; (2) isolation of the pNm derivatives, as a group, by anion-exchange chromatography on DEAE-cellulose; (3) resolution of the individual pNm compounds by two-dimensional paper chromatography; (4) identification and quantitative measurement of pNm derivatives by ultraviolet absorption spectrophotometry. Using this procedure, the molar proportions of the Nm constituents of wheat embryo, yeast, and Escherichia coli tRNA have been determined. The close correspondence between the values measured by venom hydrolysis and those obtained by analysis of alkali-stable dinucleotide (Nm-Np) sequences attests to the validity of the venom assay, and further indicates that alkali-stable sequences larger than dinucleotides are not present in significant amounts in the tRNA of the above three organisms. During the present investigation, several ultraviolet-absorbing components, not immediately identifiable as ribose-methylated nucleotides, were isolated along with the expected O2-methylnucleoside 5-phosphates. Preliminary characterization of one of these compounds suggests that it is a derivative of a novel nucleoside, O2-methyl-5-carboxymethyluridine (cm5Um is released as part of an alkali-stable dinucleotide, cm5Um-Ap. The proportion of pU-2 in venom hydrolysates of yeast tRNA (0.02 mol percent, the same as the content of cm5Um-Ap in alkaline hydrolysates) suggests that O2-methyl-5-carboxymethyluridine may be confined to a single isoaccepting species of tRNA in yeast. In an allied study, reinvestigation of the alkali-stable dinucleotide sequences of baker's yeast tRNA has confirmed previous results concerning the sequence distribution of O2-methylribose in yeast tRNA (Gray, M. W. & Lane, B.G. (1967) Biochim. Biophys. Acta 134, 243-257).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0008-4018
pubmed:author
pubmed:issnType
Print
pubmed:volume
53
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
735-46
pubmed:dateRevised
2009-10-27
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
Analysis of O2'-methylnucleoside 5'-phosphates in snake venom hydrolysates of RNA: identification of O2'-methyl-5-carboxymethyluridine as a constituent of yeast transfer RNA.
pubmed:publicationType
Journal Article