Abstract:
:E. coli C6 rel- met- cys- was cultured in a fully supplemented medium and in media lacking cysteine or methionine. tRNA isolated from the three cultures containted, respectively, a normal complement of modified nucleosides; a deficiency in thiolated nucleosides and a deficiency in methylated nucleosides. Both sulfur-deficient tRNA and methyl-deficient tRNA contained large amounts of N-6- (delta-2-isopentenyl) adenosine and small amounts of the 2-methylthio derivative. Methyl-deficient tRNA contained, in addition a large amount of a cytokinin active, differently modified nucleoside that is believed to be a sulfur derivative of N6-(delta-2-isopentenyl) adenosine. The structure of this compound is unknown. When methly-deficient tRNA and the precusor the tRNA-Tyr su3-+ A25 were enzymatically methylated in vitro, methyl groups were incorporated into derivatives of isopentenyladenosine. These results indicate that the biosynthesis of the 2-methylthio derivative of isopentenyladenosine may occur in a sequential manner, i.e., thiolation of isopentenyladenosine followed by methylation.
journal_name
Nucleic Acids Resjournal_title
Nucleic acids researchauthors
Agris PF,Armstrong DJ,Schäfer KP,Söll Ddoi
10.1093/nar/2.5.691subject
Has Abstractpub_date
1975-05-01 00:00:00pages
691-8issue
5eissn
0305-1048issn
1362-4962journal_volume
2pub_type
杂志文章abstract::Interest in secondary metabolites such as RiPPs (ribosomally synthesized and posttranslationally modified peptides) is increasing worldwide. To facilitate the research in this field we have updated our mining web server. BAGEL4 is faster than its predecessor and is now fully independent from ORF-calling. Gene clusters...
journal_title:Nucleic acids research
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journal_title:Nucleic acids research
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journal_title:Nucleic acids research
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journal_title:Nucleic acids research
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journal_title:Nucleic acids research
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更新日期:2014-01-01 00:00:00
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