کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10799334 | 1054316 | 2005 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Porphyrins and porphines bind strongly and specifically to tRNA, precursor tRNA and to M1 RNA and inhibit the ribonuclease P ribozyme reaction
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کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شیمی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Porphyrins and porphines strongly inhibit the action of the RNA subunit of the Escherichia coli ribonuclease P (M1 RNA). Meso-tetrakis(N-methyl-pyridyl)porphine followed linear competitive kinetics with pre-tRNAGly1 from E. coli as variable substrate (Ki 0.960 μM). Protoporphyrin IX showed linear competitive inhibition versus pre-tRNAGly1 from E. coli (Ki 1.90 μM). Inhibition by meso-tetrakis[4-(trimethylammonio)phenyl]porphine versus pre-tRNAGly1 from E. coli followed non-competitive kinetics (Ki 4.1 μM). The porphyrins bound directly to E. coli tRNAVal, E. coli pre-tRNAGly1 and M1 RNA and dissociation constants for the 1:1 complexes were determined using fluorescence spectroscopy. Dissociation constants (μM) against E. coli tRNAVal and E. coli pre-tRNAGly were: meso-tetrakis(N-methyl-pyridyl)porphine 1.21 and 0.170; meso-tetrakis[4-(trimethylammonio)phenyl]porphine, 0.107 and 0.293; protoporphyrin IX, 0.138 and 0.0819. For M1 RNA, dissociation constants were 32.8 nM for meso-tetrakis(N-methyl-pyridyl)porphine and 59.8 nM for meso-tetrakis[4-(trimethylammonio)phenyl]porphine and excitation and emission spectra indicate a binding mode with strong Ï-stacking of the porphine nucleus and base pairs in a rigid low-polarity environment. Part of the inhibition of ribonuclease P is from interaction with the pre-tRNA substrate, resulting from porphyrin binding to the D-loop/T-loop region which interfaces with M1 RNA during catalysis, and part from the porphyrin binding to the M1 RNA component.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression - Volume 1730, Issue 1, 25 July 2005, Pages 47-55
Journal: Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression - Volume 1730, Issue 1, 25 July 2005, Pages 47-55
نویسندگان
Yoshiaki Hori, Maria C. Rogert, Terumichi Tanaka, Yo Kikuchi, Elena V. Bichenkova, Amanda N. Wilton, Abdul Gbaj, Kenneth T. Douglas,