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The Journal of Antibiotics Jan 1969
Topics: Chemical Phenomena; Chemistry; Computers; Crystallography; Molecular Weight; Viomycin
PubMed: 4305865
DOI: 10.7164/antibiotics.22.34 -
Biophysical Journal May 2011Transfer RNA (tRNA) translocates inside the ribosome during translation. We studied the interaction strengths between the ribosome and tRNA at various stages of...
Transfer RNA (tRNA) translocates inside the ribosome during translation. We studied the interaction strengths between the ribosome and tRNA at various stages of translocation. We utilized an optical trap to measure the mechanical force to rupture tRNA from the ribosome. We measured the rupture forces of aminoacyl tRNA or peptidyl tRNA mimic from the ribosome in a prepeptidyl transfer state, the pretranslocational state, and the posttranslocational state. In addition, we measured the interaction strength between the ribosome and aminoacyl-tRNA in presence of viomycin. Based on the interaction strengths between the ribosome and tRNA under these conditions, 1), we concluded that tRNA interaction with the 30S subunit is far more important than the interaction with the 50S subunit in the mechanism of translocation; and 2), we propose a mechanism of translocation where the ribosomal ratchet motion, with the aid of EF-G, drives tRNA translocation.
Topics: Escherichia coli; Peptide Chain Elongation, Translational; Protein Biosynthesis; RNA, Transfer; RNA, Transfer, Amino Acyl; Ribosomes
PubMed: 21539788
DOI: 10.1016/j.bpj.2011.03.023 -
Journal of Biochemistry May 1982Precise immunological recognition of anti-viomycin antiserum at detailed parts in the structure of viomycin was studied by cross reactivities of the antiserum to...
Precise immunological recognition of anti-viomycin antiserum at detailed parts in the structure of viomycin was studied by cross reactivities of the antiserum to viomycin and its ten analogs using an enzyme immunoassay of viomycin. The antiserum clearly recognized all minor modifications in the sixteen membered ring of viomycin, indicating that the antiserum clearly recognizes the whole structure of the sixteen membered ring. Recognition of the antiserum on the beta-lysine terminus was also examined showing that the antiserum was also recognized on this part. Thus, the anti-viomycin antiserum was deduced to recognize the whole structure of viomycin, from which the deduction was made that the anti-viomycin antibodies in the antiserum must possess cavities fitting the whole structure of viomycin. The crystal dimensions of viomycin are 13 A in length, 8 A in width, and 7 A in depth. Thus, the high dimensional structure of the binding sites of the anti-viomycin antibodies was deduced to possess cavities of a similar size to that of viomycin.
Topics: Animals; Antigens; Binding Sites, Antibody; Cross Reactions; Immunochemistry; Immunoenzyme Techniques; Immunoglobulins; Rabbits; Viomycin
PubMed: 6284729
DOI: 10.1093/oxfordjournals.jbchem.a133851 -
The Journal of Antibiotics Oct 1976
Localization of co-resistance to streptomycin, kanamycin, capreomycin, and tuberactinomycin in core particles derived from ribosomes of viomycin-resistant Mycobacterium smegmatis.
Topics: Antibiotics, Antitubercular; Capreomycin; Drug Resistance, Microbial; Enviomycin; Kanamycin; Mutation; Mycobacterium; Ribosomes; Streptomycin; Viomycin
PubMed: 62857
DOI: 10.7164/antibiotics.29.1124 -
The Journal of Antibiotics May 1988Deoxypheganomycin D, a specific inhibitor of mycobacteria, inhibits the growth in vitro of Mycobacterium smegmatis ATCC 607 (M. 607) bacteriostatically at concentrations...
Deoxypheganomycin D, a specific inhibitor of mycobacteria, inhibits the growth in vitro of Mycobacterium smegmatis ATCC 607 (M. 607) bacteriostatically at concentrations as high as 7 X 10(-5) M. It shows no cross-resistance to paromomycin, capreomycin, viomycin, streptothricin, kanamycin and streptomycin. Deoxypheganomycin D at 2.8 X 10(-7) M where the cell growth of M. 607 is only partially inhibited does not significantly inhibit DNA, RNA or protein synthesis but leads to marked decrease (13% of control) in [14C]glycerol-derived radioactivity in cell-walls. In the presence of 7 X 10(-6) M deoxypheganomycin D, the influx of leucine but not thymidine is affected while the reverse is true with efflux. The data suggest that the effect of deoxypheganomycin D on M. 607 may be related to both the cell membrane and specific mycobacterial lipid like components of the cell-wall.
Topics: Amino Acids; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Bacterial Proteins; Cell Membrane Permeability; Cell Wall; DNA, Bacterial; Mycobacterium; Nucleic Acid Precursors; Peptides
PubMed: 3384753
DOI: 10.7164/antibiotics.41.675 -
The EMBO Journal Jul 1995Several examples of inhibition of the function of a ribozyme or RNA-protein complex have shown that certain antibiotics can interact specifically with RNA. There are,...
Several examples of inhibition of the function of a ribozyme or RNA-protein complex have shown that certain antibiotics can interact specifically with RNA. There are, however, few examples of antibiotics that have a positive, rather than a negative, effect on the function of an RNA. We have found that micromolar concentrations of viomycin, a basic, cyclic peptide antibiotic of the tuberactinomycin group, enhance the cleavage of a ribozyme derived from Neurospora VS RNA. Viomycin decreases by an order of magnitude the concentration of magnesium required for cleavage. It also stimulates an otherwise insignificant transcleavage reaction by enhancing interactions between RNA molecules. The ability of viomycin to enhance some RNA-mediated reactions but inhibit others, including translation and Group I intron splicing, demonstrates the potential for natural selection by small molecules during evolution in the 'RNA world' and may have broader implications with respect to ribozyme expression and activity in contemporary cells.
Topics: Enviomycin; Magnesium Chloride; Models, Molecular; Neurospora; Nucleic Acid Conformation; RNA Processing, Post-Transcriptional; RNA, Catalytic; RNA, Fungal; Viomycin
PubMed: 7621836
DOI: 10.1002/j.1460-2075.1995.tb07327.x -
Microbiology and Immunology 1983The mechanism of resistance of Mycobacterium intracellulare strain 103 and other clinical isolates to a variety of drugs including aminoglycoside and peptide antibiotics...
The mechanism of resistance of Mycobacterium intracellulare strain 103 and other clinical isolates to a variety of drugs including aminoglycoside and peptide antibiotics was investigated. Enzymatic inactivation of aminoglycoside and peptide antibiotics could not be demonstrated. Ribosomes of the strain were found to be sensitive to the antibiotics. The levels of resistance of strain 103 and other clinical isolates decreased dramatically when the culture medium was changed from Dubos agar to Tween 80-containing agar. These results suggest that a permeability barrier is the reason for naturally occurring resistance in M. intracellulare.
Topics: Aminoglycosides; Anti-Bacterial Agents; Cell Membrane Permeability; Chloramphenicol; Culture Media; Drug Resistance, Microbial; Kanamycin; Mycobacterium; Nontuberculous Mycobacteria; Ribosomes; Streptomycin; Viomycin
PubMed: 6312275
DOI: 10.1111/j.1348-0421.1983.tb00601.x -
European Journal of Biochemistry Dec 1986The standard technique for determination of the ribosomal site location of bound tRNA, viz. the puromycin reaction, has been analyzed with regard to its applicability...
The standard technique for determination of the ribosomal site location of bound tRNA, viz. the puromycin reaction, has been analyzed with regard to its applicability under tRNA saturation conditions. The criteria derived have been used to re-examine the exclusion principle for peptidyl-tRNA binding, which states that only one peptidyl-tRNA (AcPhe-tRNA) can be bound per ribosome although in principle two sites (A and P site) are available. The following results were obtained. The puromycin reaction is only appropriate for a site determination if the reaction conditions prevent one ribosome from performing more than one puromycin reaction. With an excess of AcPhe-tRNA over ribosomes, and in the absence of EF-G, this criterion is fulfilled at 0 degree C, where the P-site-bound material reacts with puromycin (quantitative reaction after 50 h), while the A-site-bound material does not. In contrast, at 37 degrees C the extent of the puromycin reaction can exceed the binding values by 2-4-fold ('repetitive reaction'). In the presence of EF-G a repetitive puromycin reaction is seen even at 0 degree C, i.e. EF-G can already promote a translocation reaction at 0 degree C. However, the extent of translocation becomes negligibly low for short incubation times (up to 60 min) at 0 degree C, if only catalytic amounts of EF-G are used. Using the criteria outlined above, the validity of the exclusion principle for Escherichia coli ribosomes was confirmed pursuing two different experimental strategies. Ribosomes were saturated with AcPhe-tRNA at one molecule per 70S ribosome, and a quantitative puromycin reaction demonstrated the exclusive P-site location of the AcPhe-tRNA. The same result was also found in the presence of viomycin, which blocks the translocation reaction. These findings also indicate that here nearly 100% of the ribosomes participate in AcPhe-tRNA binding to the P site. Precharging the P sites of 70S ribosomes with one Ac[14C]Phe-tRNA molecule per ribosome prevented additional Ac[3H]Phe-tRNA binding. In contrast, 70S particles carrying one molecule of [14C]tRNAPhe per ribosome were able to bind up to a further 0.64 molecule Ac[3H]Phe-tRNA per ribosome.
Topics: Binding Sites; Binding, Competitive; Kinetics; Peptide Elongation Factor G; Peptide Elongation Factors; Puromycin; RNA, Transfer, Amino Acyl; Ribosomes; Temperature; Viomycin
PubMed: 3024981
DOI: 10.1111/j.1432-1033.1986.tb10498.x -
The Journal of Antibiotics Sep 1973
Topics: Bacteria; Chemical Phenomena; Chemistry; Fungi; Oxidation-Reduction; Trichomonas; Viomycin
PubMed: 4365319
DOI: 10.7164/antibiotics.26.528 -
The Journal of Antibiotics Jul 1972
Topics: Bacteria; Microbial Sensitivity Tests; Structure-Activity Relationship; Viomycin
PubMed: 4350197
DOI: 10.7164/antibiotics.25.429