Spectinomycin is an aminocyclitol antibiotic, closely related to the aminoglycosides, produced by the bacterium Streptomyces spectabilis. Spectinomycin is produced in nature by many organisms including cyanobacteria and various plant species. It is present in the genome or plastome of many plastids as the spc operon, which is usually 2–10 amino acids long (this has been known to vary). The difference in size may be due to the elimination of obsolete genes or the takeover of its function by nuclear genes. Spectinomycin is mainly produced by organisms as a defence mechanism against predators. Spectinomycin binds to the 30S subunit of the bacterial ribosome and interrupts protein synthesis. One form of resistance has emerged in the 16S ribosomal RNA in Pasteurella multocida. It is given by injection to treat gonorrhea, especially in patients who are allergic to penicillins.
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