Pristinamycin ( INN), also spelled pristinamycine, is an

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of ...

used primarily in the treatment of staphylococcal infections, and to a lesser extent

streptococcal ''Streptococcus'' is a genus of gram-positive bacteria, gram-positive ' (plural ) or spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. Cell divisio ...

infections. It is a

streptogramin Streptogramins are a class of antibiotics. Streptogramins are effective in the treatment of vancomycin-resistant ''Staphylococcus aureus'' (VRSA) and vancomycin-resistant ''Enterococcus'' (VRE), two of the most rapidly growing strains of multidru ...

group antibiotic, similar to

virginiamycin Virginiamycin is a streptogramin antibiotic similar to pristinamycin and quinupristin/dalfopristin. It is a combination of pristinamycin IIA (virginiamycin M1) and virginiamycin S1. Virginiamycin is used in the fuel ethanol Ethanol (a ...

, derived from the bacterium ''

Streptomyces pristinaespiralis ''Streptomyces'' is the largest genus of Actinomycetota and the type genus of the family Streptomycetaceae. Over 500 species of ''Streptomyces'' bacteria have been described. As with the other Actinomycetota, streptomycetes are gram-positive, ...

''. It is marketed in Europe by Sanofi-Aventis under the trade name Pyostacine. Pristinamycin is a mixture of two components that have a synergistic antibacterial action. Pristinamycin IA is a macrolide, and results in pristinamycin's having a similar spectrum of action to

erythromycin Erythromycin is an antibiotic used for the treatment of a number of bacterial infections. This includes respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease, and syphilis. It may also be used duri ...

Pristinamycin IIA Pristinamycin IIA is a macrolide antibiotic. It is a member of the streptogramin A group of antibiotics and one component of pristinamycin (the other being pristinamycin IA). Pristinamycin IIA was first isolated from the Streptomyces virginiae, ...

(streptogramin A) is a

depsipeptide A depsipeptide is a peptide in which one or more of its amide, -C(O)NHR-, groups are replaced by the corresponding ester, -C(O)OR, Many depsipeptides have both peptide and ester linkages. Elimination of the N–H group in a peptide structure results ...

. PI and PII are coproduced by ''S. pristinaespiralis'' in a ratio of 30:70. Each compound binds to the bacterial 50 S ribosomal subunit and inhibits the elongation process of the protein synthesis, thereby exhibiting only a moderate bacteriostatic activity. However, the combination of both substances acts synergistically and leads to a potent bactericidal activity that can reach up to 100 times that of the separate components. The pristinamycin biosynthetic gene cluster is the largest antibiotic supercluster known so far, with a size of ~210 kb, wherein the PI and PII biosynthetic genes are not clustered individually but are scattered across the complete sequence region. Furthermore, this biosynthetic gene region is interrupted by a cryptic type II PKS gene cluster.

Clinical use

Despite the macrolide component, it is effective against erythromycin-resistant staphylococci and streptococci. It is active against methicillin-resistant ''Staphylococcus aureus'' (MRSA). Its usefulness for severe infections, however, may be limited by the lack of an

intravenous Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...

formulation owing to its poor solubility. Nevertheless, it is sometimes used as an alternative to

rifampicin Rifampicin, also known as rifampin, is an ansamycin antibiotic used to treat several types of bacterial infections, including tuberculosis (TB), mycobacterium avium complex, ''Mycobacterium avium'' complex, leprosy, and Legionnaires’ disease. ...

+ fusidic acid or linezolid for the treatment of MRSA. The lack of an intravenous formulation led to the development of the pristinamycin-derivative quinupristin/dalfopristin (i.e.,

Synercid Quinupristin/dalfopristin, or quinupristin-dalfopristin, (pronunciation: kwi NYOO pris tin / dal FOE pris tin) (trade name Synercid) is a combination of two antibiotics used to treat infections by staphylococci and by vancomycin-resistant ''Enter ...

), which may be administered intravenously for more severe MRSA infections.

Footnotes

{{Macrolides, lincosamides and streptogramins Combination antibiotics Depsipeptides Cyclic peptides

Clinical use

See also

Footnotes