Isoleucine:RNA sites with associated coding sequences.

I Majerfeld; M Yarus

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PubMed · 9630252

Isoleucine:RNA sites with associated coding sequences.

I Majerfeld·M Yarus

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Abstract

An RNA family that binds isoleucine with Kd = 200-500 microM was repetitively isolated from a ribonucleotide transcript pool containing 50 randomized positions. The RNA site is specific, discriminating against branched side chains of different size (valine--one methylene smaller than isoleucine) by at least 1.3 kcal/mol and against the shape (linear) of norleucine by 0.6 kcal/mol. The binding site was localized by sequence comparison, by synthesis of mutant and truncated active derivatives, and by chemical modification-interference. The binding site is small, no more than 10-12 nt, containing an asymmetric internal loop (6 over 2 nt) that includes the isoleucine codon AUU and a sequence of four G's, two of which are involved in G-U and G-C base pairs. Areas of U/G concentration like these may signal a hydrophobic RNA site.

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Amides Amino Acids Base Sequence Binding Sites Chromatography, Affinity Isoleucine Lead Molecular Sequence Data Nucleic Acid Conformation RNA Sequence Analysis, RNA Zinc Comparative Study Journal Article

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I Majerfeld, M Yarus. 1998. Isoleucine:RNA sites with associated coding sequences.. https://pubmed.ncbi.nlm.nih.gov/9630252/

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