Pristinamycin

{{Short description|Group of chemical compounds}} {{Infobox drug | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 464214518 | image = Pristinamycin IA.png | image_class = skin-invert-image | image2 = Pristinamycin IIA.svg | image_class2 = skin-invert-image  | type = combo | component1 = Pristinamycin IA | class1 = Streptogramin B antibiotic | component2 = Pristinamycin IIA | class2 = Streptogramin A antibiotic  | tradename = | Drugs.com = {{drugs.com|international|pristinamycin}} | MedlinePlus = a603007 | pregnancy_AU =  | pregnancy_US =  | pregnancy_category = | legal_AU =  | legal_CA =  | legal_UK =  | legal_US =  | legal_status = | routes_of_administration =  | CAS_number_Ref = {{cascite|changed|??}} | CAS_number = 270076-60-3 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = 4O8O7Q7IU4 | ATCvet = | ATC_prefix = J01 | ATC_suffix = FG01 | PubChem = 11979535 | DrugBank_Ref = {{drugbankcite|correct|drugbank}} | DrugBank = | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 10152812 | ChEMBL_Ref = {{ebicite|changed|EBI}} | ChEMBL = 1256399  }}

'''Pristinamycin''' (INN), also spelled '''pristinamycine''', is an antibiotic used primarily in the treatment of staphylococcal infections, and to a lesser extent streptococcal infections. It is a streptogramin group antibiotic, similar to virginiamycin, derived from the bacterium ''Streptomyces pristinaespiralis''. 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 IIA is a macrolide, and results in pristinamycin's having a similar spectrum of action to erythromycin. Pristinamycin IA (streptogramin B) is a depsipeptide.<ref name="Hamilton-Miller1991">{{cite journal | vauthors = Hamilton-Miller JM | title = From foreign pharmacopoeias: 'new' antibiotics from old? | journal = The Journal of Antimicrobial Chemotherapy | volume = 27 | issue = 6 | pages = 702–705 | date = June 1991 | pmid = 1938680 | doi = 10.1093/jac/27.6.702 | doi-access = free }}</ref> 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.<ref name="pmid21342465">{{cite journal | vauthors = Mast Y, Weber T, Gölz M, Ort-Winklbauer R, Gondran A, Wohlleben W, Schinko E | title = Characterization of the 'pristinamycin supercluster' of Streptomyces pristinaespiralis | journal = Microbial Biotechnology | volume = 4 | issue = 2 | pages = 192–206 | date = March 2011 | pmid = 21342465 | pmc = 3818860 | doi = 10.1111/j.1751-7915.2010.00213.x }}</ref> Furthermore, this biosynthetic gene region is interrupted by a cryptic type II PKS gene cluster.

==Medical use== Despite the macrolide component, it is effective against erythromycin-resistant staphylococci and streptococci.<ref name="Weber2001">{{cite journal | vauthors = Weber P | title = [Streptococcus pneumoniae: lack of emergence of pristinamycin resistance] | journal = Pathologie-Biologie | volume = 49 | issue = 10 | pages = 840–845 | date = December 2001 | pmid = 11776696 | doi = 10.1016/S0369-8114(01)00255-3 }}</ref><ref name="Leclercq2003">{{cite journal | vauthors = Leclercq R, Soussy CJ, Weber P, Moniot-Ville N, Dib C | title = [In vitro activity of the pristinamycin against the isolated staphylococci in the french hospitals in 1999-2000] | journal = Pathologie-Biologie | volume = 51 | issue = 7 | pages = 400–404 | date = September 2003 | pmid = 12948760 | doi = 10.1016/S0369-8114(03)00054-3 }}</ref> It is active against methicillin-resistant ''Staphylococcus aureus'' (MRSA). Its usefulness for severe infections, however, may be limited by the lack of an intravenous formulation owing to its poor solubility.<ref name="Martindale34">{{cite book | editor=Sean C. Sweetman | title=Martindale: The complete drug reference | edition=34th | date=November 30, 2004 | publisher=Pharmaceutical Press | location=London | isbn= 0-85369-550-4| title-link=Martindale: The complete drug reference }}</ref> Nevertheless, it is sometimes used as an alternative to rifampicin+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), which may be administered intravenously for more severe MRSA infections.

== Footnotes == {{reflist}}

Category:Combination antibiotics Category:Depsipeptides Category:Cyclic peptides