Quinupristin is a streptogramin antibiotic. Quinupristin blocks peptide bond synthesis to prevent the extension of polypeptide chains and promote the detachment of incomplete protein chains in the bacterial ribosomal subunits^{[1] [2]}. In Vitro: Quinupristin/dalfopristin is a combination of streptogramin antibiotics used to against infections. Quinupristin/dalfopristin targets the 23S rRNA of most Gram-positive bacteria as well as those of certain Gram-negative bacteria^[1].
Quinupristin/dalfopristin is reportedly effective against Mycoplasma spp^[1].