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W J Burrows

Publications and source records attributed to W J Burrows.

13 recordsLinked to original sources
PubMed1978

Cytokinins.

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Allosteric Regulation↗
PubMed1970

Identification of the cytokinin-active ribonucleosides in pure Escherichia coli tRNA species.

The distribution of the two cytokinin-active ribonucleosides 6-(3-methyl-2-butenylamino)-9-beta-D-ribofuranosylpurine (1) and 6-(3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuranosylpurine (2) in tRNA(Phe), tRNA(UUG) (Leu), tRNA(UCR) (Ser), tRNA(Tyr), tRNA(Cys), and tRNA(2) (Trp) from stationary phase Escherichia coli has been studied. Compound 2 predominated in all these species except tRNA(Phe), in which compound 1 was greatly in excess. Compound 1 was present in relatively small amounts in tRNA(UUG) (Leu), tRNA(Cys), and tRNA(2) (Trp), and was not detected in tRNA(UCR) (Ser) and tRNA(Tyr). Cells from the early logarithmic phase had the highest cytokinin content in their tRNA. Stationary phase tRNA had a slight increase in the amount of 1, which may be explained by the appearance of the new tRNA(Phe). No differences were observed between the chromatographic patterns of tRNAs from early-, mid-, and latelogarithmic phases.

Amino Acids↗
PubMed1969

Cytokinin of wheat germ transfer RNA: 6-(4-hydroxy-3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuranosylpurine.

A new modified nucleoside is responsible, in part, for the cytokinin activity of transfer RNA from wheat germ. The structure as judged by mass spec-trometry is 6-(4-hydroxy-3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuran-osylpurine. Unequivocal synthesis afforded material having ultraviolet, mass spectral, and chromatographic properties identical with those of the natural product.

Chromatography↗
PubMed1969

Cytokinins: distribution in transfer RNA species of Escherichia coli.

This distribution of cytokinin activity in tRNA species of Escherichia coli has been determined. Cytokinin activity was restricted to tRNA species recognizing codons with the initial letter U. The following have been shown to contain a cytokinin: tRNA(Phe), tRNA(Leu) UUG, tRNA(Ser)UC(G) (A), tRNA(Tyr), and tRNA(Try). tRNA(Cys) was present in fractions with cytokinin activity but was not sufficiently pure to prove it to be active. One tRNA(Ser) UC(C) (U) species was inactive. All major tRNA species recognizing condons with initial letters other than U were devoid of cytokinin activity in the tobacco bioassay. The significance of these findings is discussed as providing a possible mechanism of quantitative modulation at the translation stage of gene-controlled protein biosynthesis.

Cell Division↗
PubMed1968

Cytokinin from soluble RNA of Escherichia coli: 6-(3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuranosylpurine.

We have isolated a compound responsible for the cytokinin activity of soluble RNA from Escherichia coli. The structure, indicated as 6-(3-methyl-2-butenylamino)-2-methylthio-9-beta-D-ribofuranosylpurine, C(16)H(23)N(5)0(4)S, on the basis of low-and high-reso!ution mass spectrometry, was established by unequivocal synthesis. The mass spectra, chromatographic behavior, and ultraviolet spectra of the compounds from natural and synthetic sources were identical.

Chromatography, Paper↗