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Streptomycin
[[File:Streptomycin Molecular Structure.jpg|thumb|Streptomycin molecular Structure
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Streptomycin is a broad spectrum aminoglycoside antibiotic typically used for treatment of active tuberculosis, always in combination with other antituberculosis agents. Streptomycin is usually used in combination with agents that are known to be hepatotoxic and the role of streptomycin in liver injury has been difficult to assess,but most information suggests that streptomycin is not hepatotoxic. It irreversibly binds to the 16S rRNA and S12 protein within the bacterial 30S ribosomal subunit and as a result, this agent interferes with the assembly of initiation complex between mRNA and the bacterial ribosome, thereby inhibiting the initiation of protein synthesis. In addition, streptomycin induces misreading of the mRNA template and causes translational frameshift,thereby resulting in premature termination. This eventually leads to bacterial cell death.

Biosynthesis
Streptomycin is composed of three molecular components: aminocyclitol(streptidine), 6-deoxyhexose(streptose), and N-methyl-L-glucosamine moeities, which they are all derived from D-glucose. Streptidine, is an amino cyclitol that is scycllo-inositol in which the hydroxy groups at positions 1 and 3 and replaced by guanidino. The streptidine moiety is synthesized via myo-inositol (member of the vitamin B-complex), which is then oxidized at C-1 and transaminated to give its scyllo-inosamine identity. After phosphorylation, the compound is transamidinated by arginine and this process is repeated at the C-3 position. Streptose is a deoxypentose that is made from D-glucose via a dTDP-glucose pathway. Biosynthetic route for N-methyl-L-glucosamine moiety is unknown despite the fact that a biosynthetic gene cluster have been proposed.