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Biochemistry Nov 2010Telomeric DNA sequences have been at the center stage of drug design for cancer treatment in recent years. The ability of these DNA structures to form four-stranded...
Telomeric DNA sequences have been at the center stage of drug design for cancer treatment in recent years. The ability of these DNA structures to form four-stranded nucleic acid structures, called G-quadruplexes, has been perceived as target for inhibiting telomerase activity vital for the longevity of cancer cells. Being highly diverse in structural forms, these G-quadruplexes are subjects of detailed studies of ligand-DNA interactions of different classes, which will pave the way for logical design of more potent ligands in future. The binding of aminoglycosides was investigated with Oxytricha nova quadruplex forming DNA sequence (GGGGTTTTGGGG)(2). Isothermal titration calorimetry (ITC) determined ligand to quadruplex binding ratio shows 1:1 neomycin:quadruplex binding with association constants (K(a)) ∼ 10(5) M(-1) while paromomycin was found to have a 2-fold weaker affinity than neomycin. The CD titration experiments with neomycin resulted in minimal changes in the CD signal. FID assays, performed to determine the minimum concentration required to displace half of the fluorescent probe bound, showed neomycin as the best of the all aminoglycosides studied for quadruplex binding. Initial NMR footprint suggests that ligand-DNA interactions occur in the wide groove of the quadruplex. Computational docking studies also indicate that aminoglycosides bind in the wide groove of the quadruplex.
Topics: Aminoglycosides; Animals; Base Sequence; Calorimetry; DNA, Protozoan; Framycetin; Guanine; Hydrogen Bonding; Ligands; Magnetic Resonance Spectroscopy; Models, Molecular; Neomycin; Oxytricha; Paromomycin; Ribostamycin; Spectrophotometry, Ultraviolet
PubMed: 20886815
DOI: 10.1021/bi101517e -
The Journal of Antibiotics May 1979Microelectrophoresis was found to be a rapid method for studying the interaction between aminoglycoside antibiotics and liposomes prepared from acid phospholipids. The...
Microelectrophoresis was found to be a rapid method for studying the interaction between aminoglycoside antibiotics and liposomes prepared from acid phospholipids. The ability to cause charge reversal of liposomes prepared from phosphatidyl inositol was ranked in the order neomycin greater than gentamicin greater than tobramycin greater than amikacin greater than kanamycin greater than ribostamycin greater than streptomycin greater than dihydrostreptomycin greater than Ca2+. Similar results were obtained with liposomes prepared from a mixture (8: 2) of phosphatidyl choline and phosphatidic acid, but no effect was detectable with neutral liposomes made from phosphatidyl choline only. The results support the view that the attraction between positively charged nitrogen groups on the antibiotics and the negatively charged groups of acidic phospholipids are predominantly responsible for the interaction. Extension of the studies to ionic strengths and calcium concentrations similar to those found in vivo showed a reduction, but not elimination, of the observed effects.
Topics: Aminoglycosides; Anti-Bacterial Agents; Drug Interactions; Electrophoresis; Liposomes; Phospholipids
PubMed: 528396
DOI: 10.7164/antibiotics.32.504 -
Antimicrobial Agents and Chemotherapy Jan 1980We have tested the effect of five aminoglycoside antibiotics (gentamicin, sisomicin, tobramycin, ribostamycin, and amikacin) on the candidacidal activity of human... (Comparative Study)
Comparative Study
We have tested the effect of five aminoglycoside antibiotics (gentamicin, sisomicin, tobramycin, ribostamycin, and amikacin) on the candidacidal activity of human neutrophils in vitro; all of them are inhibitory and can be grouped into three significantly different levels of toxicity. Gentamicin in the most toxic and sisomicin is the least toxic.
Topics: Amikacin; Aminoglycosides; Candida; Gentamicins; Humans; Neutrophils; Ribostamycin; Sisomicin; Tobramycin
PubMed: 7352753
DOI: 10.1128/AAC.17.1.87 -
Zhongguo Yao Li Xue Bao = Acta... Jan 1986
Topics: Animals; Anti-Bacterial Agents; Cats; Diaphragm; Female; In Vitro Techniques; Male; Membrane Potentials; Mice; Muscle Contraction; Neuromuscular Junction; Rats; Ribostamycin; Synaptic Transmission; Vas Deferens
PubMed: 3020871
DOI: No ID Found -
The Journal of Antibiotics Jan 1980
Topics: DNA, Bacterial; Kanamycin; Microscopy, Electron; Molecular Weight; Plasmids; Ribostamycin; Streptomyces
PubMed: 7372545
DOI: 10.7164/antibiotics.33.118 -
The Journal of Antibiotics Jun 1975
Topics: Acetylation; Acetyltransferases; Amikacin; Aminoglycosides; Butirosin Sulfate; Chemical Phenomena; Chemistry; Gentamicins; Kanamycin; Microbial Sensitivity Tests; Neomycin; Pseudomonas aeruginosa; Ribostamycin; Tobramycin
PubMed: 50311
DOI: 10.7164/antibiotics.28.486