Tobramycin structure

Structures of Neomycin and Tobramycin in Complex with RNA Aptamers... 

The structures of tobramycin and neomycin B in complex with aptamer RNAs also display the importance of interactions between the amino groups of aminoglycosides and the phosphate backbone of RNA. In the neomycin-aptamer complex, the 6 -amino group on ring I interacts with the phosphate backbone. Paromomycin, in which the 6 position of ring I is a hydroxyl group, binds... 

Vicens, Q. Westhof, E. Crystal structure of a complex between the aminoglycoside tobramycin and an oligonucleotide containing the ribosomal decoding a site. Chem. Biol. 2002, 9, 747-755. 

Structures of several important aminoglycoside antibiotics. Ring II is 2-deoxystreptamine. The resemblance between kanamycin and amikacin and between gentamicin, netilmicin, and tobramycin can be seen. The circled numerals on the kanamycin molecule indicate points of attack of plasmid-mediated bacterial transferase enzymes that can inactivate this drug. , , and , acetyltransferase , phosphotransferase , adenylyltransferase. Amikacin is resistant to modification at , , , and . 

ANTIBIOTICS AMINOGLYCOSIDES. The term aminoglycoside is commonly used to refer to members of the class of antibacterial antibiotics, the structures of which are derived from n-streptamine (1. R=OH), r>-2-deoxystreptamine (I, R=H), or closely related compounds. The term aminocyclitoi is also sometimes used to identify this group of compounds. A typical member of this class, tobramycin, lias the structure (2),... 

Figure 7.14 shows the structure of tobramycin and the sites where the antibiotic can be N-acetylated by (i) kanamycin acetyl transferase, (ii)... 

Figure 7.14. The structure of tobramycin. The arrows indicate the groups which can he N-acetylated by (a) kanamycin acetyltransferase (b) gentamycirt acetyltransferase II and (c) gentamycin acetyltransferase I...

The aminoglycoside antibiotics include streptomycin, neomycin, gentamicin, amikacin, tobramycin and kanamycin. They have a chemical structure of amino sugars joined by a glycoside... 

Tobramycin is structurally related to kanamycin and has four times the activity of gentamicin against Pseudomonas spp. It is an extremely expensive drug. Its use in animals is usually limited to the topical treatment of melting comeal ulcers caused by gentamicin-resistant Pseudomonas spp. using the ophthalmic solution approved for use in humans. 

Factors 4 and 4 are 6"-0-carbamoylkanamycin B aad kanamycin B. respectively factors 5 and 6 arc 6"-0-ar-bamoyltobramycin and tobramycin and factor 2 is upni-mycin, a tetracyclic aminoglycoside with an unu.sual bicyclic central ring structure. Kanamycin B and tobramycin probably do not occur in fermentation broths per sc but are fonned by hydrolysis of the 6-0"-carbamoy I derivatives in the isolation procedure. 

Aminoglycoside antibiotics contain amino sugars in their structure. Deoxystreptamine-containing members are neomycin, framycetin, gentamicin, kanamycin, tobramycin, amikacin, netilmicin and sisomicin. Both streptomycin and dihydrostreptomycin contain streptidine, whereas the aminocycli-... 

Figure 7 (a) Structures of tobramycin and the 40-nucleotide RNA sequence (J6fl). (b)... 

Figure 8 The NMR structure of the tobramycin-RNA complex. Tobramycin is shown by the capped-stick presentation. A portion of the RNA structure at the aminoglycoside binding...

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