Showing papers on "Ribostamycin published in 1983"

Mapping of the gene specifying aminoglycoside 3'-phosphotransferase II on the Pseudomonas aeruginosa chromosome.

Abstract: We examined the aminoglycoside inactivation enzymes in Pseudomonas aeruginosa strains, seven clinical isolates and seven laboratory strains without plasmids. All strains were found to possess the enzyme aminoglycoside 3'-phosphotransferase II [APH(3')-II]. We isolated an APH(3')-II-deficient mutant from a PAO strain by mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine. By plasmid (FP5 or R68.45)-mediated conjugation, we determined the locus of the gene specifying the APH(3')-II between trp-6 and pro-82 on the PAO chromosome and designated this gene aphA. It was concluded that the intrinsic resistance of P. aeruginosa to kanamycins, neomycins, paromomycins, ribostamycin, and butirosins was due to this newly determined gene.

Cloning of antibiotic-resistance genes in Streptomyces.

Abstract: Antibiotic-resistance genes were shotgun cloned from antibiotic-producing Streptomyces sp. using pock-forming plasmids (pSF689 and pSF765), as cloning vectors. Streptomyces chartreusis SF1623 and S. lividans 66 were used as host strains. The ribostamycin (RSM) resistance gene was cloned from S. ribosidificus SF733 DNA (on a 2.3 Md PstI fragment) into both S. chartreusis SF1623 and S. lividans 66, using pSF689 as vector. Kanamycin (KM), novobiocin (NB), destomycin (DM) and racemomycin (RM) resistance genes were cloned from S. kanamyceticus M1164, S. spheroides M1469, S. rimofaciens M1470 and S. lavendulae A249 genomic DNA into S. lividans 66, using pSF765 as vector. Furthermore two types of KM resistance determinants derived from S. kanamyceticus M1164 were cloned using S. lividans 66, the pSF689 vector. The RSM resistance gene showed no homology to plasmid pSF733 of S. ribosidificus SF733, but hybridized to PstI or BclI digested total DNA of S. ribosidificus SF733.

Multiple resistance to aminoglycoside antibiotics in actinomycetes.

Abstract: Actinomycetes were characterized in terms of resistance to 11 different aminoglycoside antibiotics (AGs). Strains freshly isolated in AG containing media showed wide varieties of multiple AG resistance, while the majority of ISP (International Streptomyces Project) cultures and the actinomycete strains isolated in an AG free medium were susceptible to all or most of the AGs tested. Marked characteristics were noted in multiple AG resistance of gray and yellow colored actinomycetes and AG-producing strains. In gray colored isolates, multiple resistance to kanamycin A, dibekacin, ribostamycin, butirosin A, istamycin A and neamine was often observed. Yellow colored isolates having multiple AG resistance were mostly resistant to neamine, ribostamycin and streptomycin and, to a lesser extent, istamycin A, dibekacin and butirosin A. Most of the AG producers tested showed unique multiple AG resistance patterns.

In vitro activity of ribostamycin against Prototheca sp.

Abstract: The in vitro activity of ribostamycin against algae of the genus Prototheca was evaluated by minimum inhibitory concentration (MIC) studies on solid media. Concentrations of 4 mcg/ml were required to inhibit 100% of the P. zopfii strains; 16 mcg/ml inhibited 100% of the P. stagnora strains and 95% of the P. wickerhamii strains. These values are inferior to plasma concentrations obtained after injection of ribostamycin. It is likely that this antibiotic could be effective in the treatment of protothecosis in man.

Identification of Tn2401, a transposon encoding multiresistance to aminoglycosides.

Abstract: Summary: A transposable element, Tn2401, was found in a clinical isolate of Pseudomonas aeruginosa. Tn2401 had a size of 7190 nucleotides and encoded aminoglycoside 3′-phosphotransferase and aminoglycoside 6′-N-acetyltransferase. The sequence encoding the former enzyme was homologous with that of Tn903. Pseudomonas aeruginosa strains harbouring this transposon were resistant to kanamycin, neomycin, lividomycin, ribostamycin, paromomycin, netilmycin, tobramycin, dibekacin, gentamicin, sisomicin, and butirosin.

Newer Methods for Characterization of Antibiotics I: Stable Isotopes in the Study of Antibiotic Synthesis

Abstract: Precursors singly and doubly labeled with stable isotopes can be used to study both the origins of antibiotic molecules and the mechanisms involved in their biosyntheses. In this review, the versatile methodology used for these approaches is discussed, using examples from the biosynthetic investigations of neomycin, ribostamycin, nybomycin and erythromycin and of two antibiotics containing the so–called m–C7N unit, pactamycin and gel–danamycin. *The E. R. Squibb Lectures on Chemistry of Microbial Products presented at Waksman Institute of Microbiology, Rutgers University, New Brunswick, N.J. March 16, 17, 1983.

Animal studies on the reduction of aminoglycoside-induced nephrotoxicity by D-glucaro-1,5-lactam.

Abstract: We studied the effect of D-glucaro-1,5-lactam on aminoglycoside-induced nephrotoxicity in rats. Parameters of nephrotoxicity were urinary excretion of tubule cells and malate dehydrogenase. When given in appropriate doses, either i. m. or via an oral tube, D-glucaro-1,5-lactam significantly reduced the excretion of cells and enzymes during the administration of gentamicin, tobramycin, dibekacin, netilmicin and ribostamycin. It did inot impair the therapeutic efficacy of ribostamycin in the experimental treatment of acute pyelonephritis in rats. The protective effect of D-glucaro-1,5-lactam could be ascribed to its inhibition of β-glucuronidase, an enzyme which is located in renal lysosomes and which is activated by aminoglycosides.