Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.26.5 (
RNase P
)
1,348
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The reaction of wild-type and two mutant derivatives of
RNase P
have been examined with wild-type and mutant substrates. We show that a mutant derivative of tRNA(Tyr)Su3, tRNA(Tyr)Su3A15, in which the G15.
C48
(57) base-pair essential for folding of the tRNA moiety is altered, is a temperature-sensitive suppressor in vivo. The precursor to tRNA(Tyr)Su3A15 is cleaved in a temperature-sensitive manner in vitro by
RNase P
and with a higher Km compared to the precursor to tRNA(Tyr)Su3. The precursor to tRNA(Tyr)Su3A2, another temperature-sensitive suppressor in vivo in which the G2.C71(80) base-pair in the acceptor stem is changed to A2.C71(80), behaves like the precursor to tRNA(Tyr)Su3 in vitro; that is, it is not cleaved in a temperature-sensitive manner. Therefore, there are at least two ways in which a suppressor tRNA can acquire a temperature-sensitive phenotype in vivo. One of the mutant derivatives of
RNase P
we have tested, rnpA49, which affects the protein cofactor of the enzyme, has a decreased kcat compared to wild-type, which can explain its phenotype in vivo.
...
PMID:Reaction in vitro of some mutants of RNase P with wild-type and temperature-sensitive substrates. 247 62
A 77-mer RNA with the sequence of Eschlerichia coli tRNA(Asp) has been chemically synthesised using standard automated phosphoramidite chemistry with the coupling reagent 4,5-dicyanoimidazole (DCI). The synthesis was carried out on a 1000 A CPG-column and. after deprotection and gel purification, a yield of about 7 mmol with a purity of > 95% was reproducibly obtained. By comparing automated synthesis of the 77-mer RNA using 1H-tetrazole and DCI as activator, DCI is advantageous in producing longer RNAs. However, for shorter RNAs ( <40 mer) no difference could be observed. In addition to the all-ribo tRNA(Asp) carrying the wild-type sequence, two variants were synthesised, one with a single C to G48 mutation and the second with a 2'-deoxy modification at
C48
. The three tRNAs were tested for their aminoacylation efficiency and high affinity binding to E. coli
RNase P
RNA. The results demonstrate that chemically synthesised 77-mer oligoribonucleotides can be successfully used for structure function studies.
...
PMID:Chemical synthesis and biological investigation of a 77-mer oligoribonucleotide with a sequence corresponding to E. coli tRNA(Asp). 1119 45