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The Tohoku Journal of Experimental... Dec 1975Neuromuscular blocking properties of ribostamycin (1 gm), dibecacin (100 mg) and tobramycin (60 mg) were studied in a man during anesthesia and surgery by observing the...
Neuromuscular blocking properties of ribostamycin (1 gm), dibecacin (100 mg) and tobramycin (60 mg) were studied in a man during anesthesia and surgery by observing the effects of these antibiotics on muscle twitch tension. These drugs alone did not show any neuromuscular blocking action in those therapeutic doses. However, during the recovery phase of d-tubocurarine block the intravenous administration of 1 gm of ribostamycin caused a fairly rapid decrease in twitch tension. Tobramycin 60 mg did not show any remarkable effect, but dibecacin 100 mg produced a slight potentiating effect on the action of d-tubocurarine. The enhancement of the action of d-tubocurarine was antagonized promptly by edrophonium and more slowly by calcium.
Topics: Anti-Bacterial Agents; Dibekacin; Drug Synergism; Humans; Muscle Contraction; Neuromuscular Blocking Agents; Ribostamycin; Tobramycin; Tubocurarine
PubMed: 1209618
DOI: 10.1620/tjem.117.399 -
The Journal of Antibiotics Jun 1999The 2-deoxystreptamine aglycon is a common structural feature found in aminocyclitol antibiotics including neomycin, kanamycin, tobramycin, gentamicin, sisomicin,...
Molecular cloning of the gene for the key carbocycle-forming enzyme in the biosynthesis of 2-deoxystreptamine-containing aminocyclitol antibiotics and its comparison with dehydroquinate synthase.
The 2-deoxystreptamine aglycon is a common structural feature found in aminocyclitol antibiotics including neomycin, kanamycin, tobramycin, gentamicin, sisomicin, butirosin and ribostamycin. A key enzyme involved in the biosynthesis of the 2-deoxystreptamine moiety is 2-deoxy-scyllo-inosose (DOI) synthase which catalyses the carbocycle formation from D-glucose-6-phosphate to 2-deoxy-scyllo-inosose. The recent success of isolating the 2-deoxy-scyllo-inosose synthase from Bacillus circulans prompted us to clone the gene responsible for this important enzyme by the use of reverse genetics approach. With the aid of DNA probes constructed on the basis of the amino-terminal sequence of the purified 42 kDa subunit of the enzyme, the responsible gene btrC was successfully cloned. Subsequently the btrC gene was heterologously expressed in Escherichia coli, and the 2-deoxy-scyllo-inosose synthase activity of the recombinant polypeptide was confirmed by chemical analysis. The btrC gene encodes a protein composed of 368 amino acids with a molecular mass of 40.7 kDa. Our previous proposal for the similarity of 2-deoxy-scyllo-inosose synthase to dehydroquinate synthase has been confirmed on the basis of their amino acid sequences. Significant differences in the sequences can also be observed however, particularly in the crucial substrate recognition regions. Comparison of the BtrC sequence with those of biosynthetic enzymes for other related microbial products is also discussed.
Topics: Amino Acid Sequence; Anti-Bacterial Agents; Bacillus; Cations, Divalent; Cloning, Molecular; Cobalt; Escherichia coli; Gene Expression; Hexosamines; Hydrogen-Ion Concentration; Kinetics; Lyases; Molecular Sequence Data; NAD; Recombinant Proteins; Sequence Alignment
PubMed: 10470681
DOI: 10.7164/antibiotics.52.559 -
European Journal of Biochemistry Jun 1981GTP hydrolysis on elongation factor (EF) Tu . ribosome complexes has been assayed in the presence of 2'(3')-O-L-phenylalanyladenosine (AdoPhe), i.e. the 3'-terminal...
Effects of antibiotics, N-acetylaminoacyl-tRNA and other agents on the elongation-factor-Tu dependent and ribosome-dependent GTP hydrolysis promoted by 2'(3')-O-L-phenylalanyladenosine.
GTP hydrolysis on elongation factor (EF) Tu . ribosome complexes has been assayed in the presence of 2'(3')-O-L-phenylalanyladenosine (AdoPhe), i.e. the 3'-terminal portion of Phe-tRNAPhe. Several requirements of the reaction have been characterized. Maximal activity is observed at 60-120 mM NH4Cl and 5-15 mM magnesium acetate. The reaction requires the free sulfhydryl group of EF-Tu normally implicated in aminoacyl-tRNA binding. Intact EF-Tu cannot be replaced by a large tryptic fragment of EF-Tu (Mr 39,000) that retains the ability to bind guanosine nucleotides. The aminoglycoside antibiotics, neomycin C and several kanamycins and gentamicins, stimulate the AdoPhe-promoted GTPase. Surprisingly, however, other closely related antibiotics, like neomycin B, paromomycin and ribostamycin, are ineffectual, thus indicating subtle differences in the actions of these antibiotics. AcPhe-tRNAPhe, bound to the ribosomal A-site, stimulates the AdoPhe-promoted GTPase, but this compound or AcTyr-tRNATyr, present in unbound form, strongly inhibits the reaction. These results suggest that N-blocked aminoacyl-tRNAs form ternary complexes with EF-Tu . GTP, which have not been previously detected because of their low stability.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Escherichia coli; Ethylmaleimide; GTP Phosphohydrolase-Linked Elongation Factors; Guanosine Diphosphate; Guanosine Triphosphate; Kinetics; Peptide Chain Elongation, Translational; Peptide Elongation Factor Tu; Peptide Elongation Factors; Peptide Fragments; RNA, Transfer, Amino Acyl; Ribosomes; Trypsin
PubMed: 6114863
DOI: 10.1111/j.1432-1033.1981.tb06298.x -
The Biochemical Journal Jun 1990The aminoglycoside phosphotransferase gene from a butirosin-producing strain of Bacillus circulans was cloned in a high-expression vector (pKK223-3) to give the...
Cloning of aminoglycoside phosphotransferase (APH) gene from antibiotic-producing strain of Bacillus circulans into a high-expression vector, pKK223-3. Purification, properties and location of the enzyme.
The aminoglycoside phosphotransferase gene from a butirosin-producing strain of Bacillus circulans was cloned in a high-expression vector (pKK223-3) to give the recombinant plasmid pMS5. Escherichia coli harbouring the plasmid, E. coli JM103[pMS5], was characterized, and several features of the expression of the phosphotransferase were studied. The phosphotransferase activity was best expressed in a medium lacking glucose, and the highest levels of the enzyme were found between 12 and 24 h of growth. The induction of the phosphotransferase expression with isopropyl beta-D-thiogalactopyranoside (inducer) was found to be undesirable as the overproduction of the enzyme led to the killing of the bacteria. The subcellular location of the phosphotransferase, and also the site in vivo of the phosphorylation of neomycin, was found to be in the cytoplasm. The phosphotransferase was purified to homogeneity in good yield (17 mg of purified protein/3 litres of culture) and was shown to be a monomer of Mr 30,000-32,000. The N-terminal amino acid sequence was in agreement with that predicted from the gene sequence and confirmed the absence of any signal sequence. The regiospecificity of the phosphotransferase reaction was studied by m.s. and by 1H-, 13C- and 31P-n.m.r. using ribostamycin as the substrate, and it was found that the antibiotic was phosphorylated at the 3'-hydroxy group.
Topics: Amino Acid Sequence; Bacillus; Base Sequence; Chemical Phenomena; Chemistry; Cloning, Molecular; Enzyme Induction; Escherichia coli; Genetic Vectors; Isopropyl Thiogalactoside; Kanamycin Kinase; Molecular Sequence Data; Phosphotransferases; Plasmids
PubMed: 2163618
DOI: 10.1042/bj2680671 -
The Journal of Antibiotics Sep 1975Microorganisms producing antibiotics have been genetically converted by earlier workers to mutants which cannot produce antibiotic without supplementation with a moiety...
Microorganisms producing antibiotics have been genetically converted by earlier workers to mutants which cannot produce antibiotic without supplementation with a moiety of the antibiotic. These antibiotics include neomycin, kanamycin, paromomycin, butirosin, sisomicin, ribostamycin and novobiocin. Success has not been reported for organisms producing guanidinocyclitol antibiotics such as streptomycin. We mutagenized conidia of the streptomycin-producing Streptomyces griseus strain 7-455F3 with nitrosoguanidine at pH 7.0. Non-producers of streptomycin were visually selected by the agar-plug technique using Bacillus subtilis. We successfully isolated mutant MIT-A5 which produces no streptomycin unless streptidine is added to the agar medium. The streptidine-dependent phenotype was confirmed in submerged culture in flasks. Attempts to produce new antibiotics by feeding aminocyclitols to mutant MIT-A5 failed. However a new antibiotic (streptomutin A) was produced by supplementation with the guanidinocyclitol, 2-deoxystreptidine. We propose the term "mutational biosynthesis" for the production of new metabolites by the use of mutants blocked in the biosynthetic pathway to the secondary metabolite. We further propose the term "idiotroph" to properly describe such mutants.
Topics: Anti-Bacterial Agents; Culture Media; Cyclohexanols; Guanidines; Hydrogen-Ion Concentration; Mutation; Phenotype; Streptomyces griseus; Streptomycin; Time Factors
PubMed: 241738
DOI: 10.7164/antibiotics.28.627 -
Antimicrobial Agents and Chemotherapy Jan 1982Of 20 clinical isolates of group A, B, G, D (Streptococcus bovis), and viridans streptococci, 5 transferred their antibiotic resistance markers into streptococcal...
Of 20 clinical isolates of group A, B, G, D (Streptococcus bovis), and viridans streptococci, 5 transferred their antibiotic resistance markers into streptococcal recipients at a low frequency (10(-4) to 10(-8)) in the apparent absence of extrachromosomal elements. All strains carried genetic markers for high-level resistance to streptomycin, kanamycin, neomycin, lividomycin A, and ribostamycin, as well as resistance to macrolides and related drugs, tetracycline, and chloramphenicol.
Topics: Aminoglycosides; Anti-Bacterial Agents; Conjugation, Genetic; Drug Resistance, Microbial; R Factors; Streptococcus; Tetracycline
PubMed: 7081973
DOI: 10.1128/AAC.21.1.176 -
The Journal of Antibiotics Dec 1973
Topics: Carbon Isotopes; Magnetic Resonance Spectroscopy
PubMed: 4792382
DOI: 10.7164/antibiotics.26.717 -
The Journal of Biological Chemistry Nov 1997Recent emergence of microbial resistance to aminoglycoside antibiotics, and the documented cytotoxicity associated with their use, calls for sustained efforts at...
Recent emergence of microbial resistance to aminoglycoside antibiotics, and the documented cytotoxicity associated with their use, calls for sustained efforts at understanding the effects of the compounds on eukaryotic cells. Using a glycosyl phosphatidylinositol (GPI)-phospholipase C (GPI-PLC) from the protozoan parasite Trypanosoma brucei, we demonstrate that a eukaryotic PLC can be activated 6-fold by aminoglycosides. Neomycin B protected GPI-PLC from a reduction in activity at pH 6.5, and increased the turnover number (kcat) of the enzyme. In structure-activity studies with the neomycin group, 2-deoxy-streptamine was mildly stimulatory; the concentration required to activate GPI-PLC 2-fold (SC200) was 310 microM. Neamine was 150-fold more active (SC200 = 2 microM) than 2-deoxy-streptamine, indicating that a 2,6-dideoxy-2, 6-diaminoglucose substituent at the 4-position of 2-deoxystreptamine plays an important role in activation of GPI-PLC. Ribostamycin and neomycin B also had SC200's of 2 microM, implying that the ribose group in ribostamycin is not involved in activation of GPI-PLC. These conclusions were affirmed in studies with Bacillus thuringiensis phosphatidylinositol-specific phospholipase C. A 2, 6-dideoxy-2,6-diaminoglucose substitution at the 4-OH of 2-deoxystreptamine activates the enzyme 17-fold, while a second 2, 6-dideoxy-2,6-diaminoglucose moiety on the ribose ring of ribostamycin provides an additional 3.5-fold stimulation. Possible implications of these observations for the effects of aminoglycosides on eukaryote cells are discussed.
Topics: Animals; Anti-Bacterial Agents; Bacillus thuringiensis; Enzyme Activation; Framycetin; Glucosamine; Glycosylphosphatidylinositol Diacylglycerol-Lyase; Hydrogen-Ion Concentration; Kinetics; Phosphatidylinositol Diacylglycerol-Lyase; Phosphoinositide Phospholipase C; Structure-Activity Relationship; Trypanosoma brucei brucei; Type C Phospholipases
PubMed: 9368017
DOI: 10.1074/jbc.272.47.29554 -
Journal of Clinical Microbiology Sep 2007Twelve strains of a rapidly growing Mycobacterium species were isolated from an outbreak associated with intramuscular injections of an antimicrobial agent and were...
Twelve strains of a rapidly growing Mycobacterium species were isolated from an outbreak associated with intramuscular injections of an antimicrobial agent and were identified by comparative sequence analysis of rpoB and hsp65. These isolates were identified as Mycobacterium massiliense (100% similarity).
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Bacterial Proteins; Chaperonin 60; Chaperonins; Child; Child, Preschool; DNA, Bacterial; DNA-Directed RNA Polymerases; Disease Outbreaks; Female; Humans; Injections, Intramuscular; Male; Middle Aged; Molecular Sequence Data; Mycobacterium; Mycobacterium Infections; Phylogeny; Ribostamycin; Sequence Analysis, DNA
PubMed: 17626174
DOI: 10.1128/JCM.00608-07 -
Journal of Clinical Microbiology Aug 1984Approximately 40% of Escherichia coli strains isolated from clinical specimens at the Institute of Medical Microbiology of the University of Zurich were resistant to...
Approximately 40% of Escherichia coli strains isolated from clinical specimens at the Institute of Medical Microbiology of the University of Zurich were resistant to kanamycin but susceptible to tobramycin in disk diffusion tests. Whereas 50% of these strains required a MIC of 7 micrograms of tobramycin per ml to inhibit 1 x 10(5) to 4 x 10(5) cells, 20% of them required a concentration of 8 micrograms or more of the drug per ml. The disk diffusion test, therefore, failed to detect resistance to tobramycin in kanamycin-resistant E. coli strains. Cell extracts from two representative strains phosphorylated and inactivated kanamycin, amikacin, gentamicin, tobramycin, 3',4'-dideoxykanamycin B (dibekacin), butirosin, lividomycin,and ribostamycin, which together constituted a novel spectrum of substrates for the enzymatic activity.
Topics: Aminoglycosides; Anti-Bacterial Agents; Drug Resistance, Microbial; Escherichia coli; Kanamycin; Kanamycin Kinase; Microbial Sensitivity Tests; Phosphorylation; Phosphotransferases; Tobramycin
PubMed: 6092419
DOI: 10.1128/jcm.20.2.295-297.1984