PubMed Health⌕ Search

Biomedical subjects

V A Erdmann

Publications and source records attributed to V A Erdmann.

At least 181 records · Page 10Linked to original sources
PubMed1977

Escherichia coli 5S RNA binding proteins L18 and L25 interact with 5.8S RNA but not with 5S RNA from yeast ribosomes.

Reconstitution experiments showed that the two Escherichia coli 5S RNA binding proteins L18 and L25 form a specific complex with yeast 5.8S RNA and not with yeast 5S RNA. The yeast 5.8S RNA-E. coli protein complex was found to exhibit ATPase and GTPase activities that had previously been observed for the E. coli 5S RNA-protein complex. The tetranucleotide UpUpCpG, which is an analog of the tRNA fragment TpsipCpG, interacted strongly with 5S RNA-protein complexes from E. coli and Bacillus stearothermophilus and weakly with yeast 5.8S RNA. UpUpCpG did not bind to E. coli, B. stearothermophilus, or yeast 5S RNA or to the yeast 5.8S RNA-E. coli protein complex. It is suggested that 5.8S RNA evolved from prokaryotic 5S RNA and that the latter two RNAs are related and have similar functions in protein synthesis.

Adenosine Triphosphatases↗
PubMed1976

Regions of tRNA important for binding to the ribosomal A and P sites.

Studies on the enzymatic inhibition of phenylalanyl-tRNAPhe and formylmethionyl-tRNAFMet binding to the ribosomes by defined tRNA fragments indicate that beside the anticodon the following regions of tRNA are important for ribosomal A-site interaction: the TppsipCp sequence, the CpCpA end, and hU loop. In contrast, binding to the ribosomal P site is not inhibited by the fragments of uncharged yeast tRNAPhe containing the hU or the TpsiC loop of the molecule. Comparative studies on the inhibitory effect of the oligonucleotides TppsipCpGp and UpUpCpGp indicate that the presence of the minor bases in TpsiC loop is not an essential prerequisite for the binding of tRNA to the ribosomal A site. Furthermore, evidence is presented that shows that the binding of the TppsipCpGp oligonucleotide to the ribosomes influences the ribosomal P site and increases there the efficiency of the codon-anticodon interaction. It is suggested that the TppsipCpGp binds to the ribosomal A site and competes there with the TpsiC loop of the aminoacyl-tRNA for the same binding site. A model for the interaction between tRNA and the ribosomal A site is proposed that involves partial unfolding of hU and TpsiC loops of the tRNA and, therefore, suggests the dynamic involvement of tRNA in protein synthesis.

Anticodon↗
PubMed1974

A new transfer RNA fragment reaction: Tp psi pCpGp bound to a ribosome-messenger RNA complex induces the synthesis of guanosine tetra- and pentaphosphates.

The tetranucleotide TpPsipCpGp, when bound to Escherichia coli 50S ribosomal subunits, can replace intact tRNA in the stringent factor-directed synthesis of guanosine tetra- and pentaphosphates. The TpPsipCpGp-dependent fragment reaction has a strict requirement for the 50S and 30S ribosomal subunits and synthetic or natural messenger RNA.

Bacterial Proteins↗