TRNA2Gln Su+2 mutants that increase amber suppression.

D Bradley; J V Park; L Soll

doi:10.1128/jb.145.2.704-712.1981

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TRNA2Gln Su+2 mutants that increase amber suppression.

D Bradley·J V Park·L Soll

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Abstract

We selected mutants of lambda pSu+2 which had an increased ability to suppress on Escherichia coli trp B9601 amber mutation on translationally stringent rpsL594 streptomycin-resistant ribosomes. tRNA2Gin Su+2 molecules produced from eight independent mutants were purified, and their ribonucleic acid sequences were determined. Two types of mutations were mapped to the tRNA2Gin Su+2(glnV) gene by this method. Both altered the pseudouridine at position 37 of the tRNA anticodon loop. Seven of the isolates were transitions (pseudouridine to cytosine), and one was a transversion (pseudouridine to adenine). These mutations resulted in Su+ transfer ribonucleic acid molecules that exhibited higher transmission coefficients than their parent Su+2 transfer ribonucleic acids. As judged by their suppressor spectra on T4 amber mutants, which were almost identical to that of Su+2, the two mutant Su+ transfer ribonucleic acids inserted glutamine at amber sites.

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Amino Acyl-tRNA Synthetases Base Sequence Escherichia coli Glutamine Mutation RNA, Transfer Substrate Specificity Suppression, Genetic Journal Article Research Support, U.S. Gov't, P.H.S.

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D Bradley, J V Park, L Soll. 1981. TRNA2Gln Su+2 mutants that increase amber suppression.. https://doi.org/10.1128/jb.145.2.704-712.1981

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