kanamisin

Kanamycin is an aminoglycoside antibiotic produced by the actinomycete Streptomyces kanamyceticus. It is mainly used to treat serious infections caused by susceptible Gram-negative bacteria and some Gram-positive cocci, often in combination with other antibiotics. It is bactericidal and acts by irreversibly binding to the 30S ribosomal subunit, causing misreading of mRNA and inhibition of protein synthesis.

In terms of spectrum, kanamycin is active against many Enterobacteriaceae and Pseudomonas species, as well as some strains of Staphylococcus aureus. It has limited activity against anaerobes. Resistance can arise through enzymatic modification of the drug, mutations in the 30S ribosomal target, or reduced uptake of the drug by the bacteria.

Administration is typically by injection, as oral absorption is poor. Topical and ophthalmic forms exist for specific indications. Kanamycin can be nephrotoxic and ototoxic, and it may cause neuromuscular blockade, particularly when used with other nephrotoxic agents. Because of these toxicities, its use for routine systemic therapy is limited, and it is generally reserved for severe infections or when other options are unsuitable. Historically, it has been used as a second-line agent in certain cases of multi-drug resistant tuberculosis, though this use has declined with newer therapies.

In laboratory and research contexts, kanamycin is used as a selectable antibiotic in molecular biology. Plasmids or cells carrying a kanamycin resistance gene (kanR) can be selected in the presence of kanamycin, enabling researchers to identify successful transformants.