Characterization of the 'pristinamycin supercluster' of Streptomyces pristinaespiralis.
Bottom Line: Furthermore, the pristinamycin gene cluster was found to be interspersed by a cryptic secondary metabolite cluster, which probably codes for a glycosylated aromatic polyketide.Gene inactivation experiments revealed that this cluster has no influence on pristinamycin production.Overall, this work provides new insights into pristinamycin biosynthesis and the unique genetic organization of the pristinamycin gene region, which is the largest antibiotic 'supercluster' known so far.
Affiliation: Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Fakultät für Biologie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany. firstname.lastname@example.orgShow MeSH
Related in: MedlinePlus
Mentions: In contrast, no such transposase genes have been reported for the virginiamycin cluster. Thus, there is no hint of a horizontal gene transfer event of the streptogramin antibiotic cluster in S. virginiae. However, so far, the virginiamycin biosynthetic gene cluster only comprises 75 kb and as some essential virginiamycin biosynthetic genes have not been identified, it seems that the cluster is still incomplete. Thus, it might be possible that there are transposase genes present in the entire cluster, which have not yet been identified (Fig. 7). In this context, it would be interesting to find out how the streptogramin biosynthetic gene clusters evolved. The high amino acid identity between numerous pristinamycin and virginiamycin specific proteins indicates that both clusters may originate from a common ancestor. Probably, a primordial actinomycete originally produced only one type of streptogramin antibiotic and the second cluster was acquired by horizontal gene transfer. To date, no strain is known that produces only one type of streptogramin. It would be interesting to identify such a strain to get more information about which cluster was acquired at first.
Affiliation: Mikrobiologie/Biotechnologie, Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Fakultät für Biologie, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany. email@example.com