title: Albicidin antibiotic and phytotoxin biosynthesis in Xanthomonas albilineans requires a phosphopantetheinyl transferase gene.
abstract: Xanthomonas albilineans produces a family of highly potent antibiotics and phytotoxins called albicidins, which are key pathogenesis factors in the systemic development of leaf scald disease of sugarcane. A gene (xabA) required for albicidin biosynthesis encodes a peptide of 278 amino acids, including the signature sequence motifs for phosphopantetheinyl transferases (PPTases) that activate polyketide and non-ribosomal peptide synthetases. The Escherichia coli entD gene, which encodes a PPTase involved in biosynthesis of enterobactin (a siderophore), restored biosynthesis of albicidin (a DNA replication inhibitor) in X. albilineans Tox- LS156 (xabA::Tn5). We conclude that XabA is a PPTase required for post-translational activation of synthetases in the albicidin biosynthetic pathway. This is the first antibiotic or toxin biosynthesis gene characterized from the genus Xanthomonas, and the first demonstration that antibiotic synthetases in the Pseudomonadaceae, like those in the Enterobacteriaceae and in Gram-positive bacteria, can require activation by a PPTase. Coupled with the recent demonstration of a separate albicidin biosynthetic gene cluster, the results indicate the possibility for overproduction of albicidins,which allows better understanding and application of these potent inhibitors of prokaryote DNA replication.
authors: Department of Botany, The University of Queensland, Brisbane 4072, Australia.
authors: G
authors: G
authors: Huang
authors: L
authors: L
authors: Zhang
authors: R G
authors: RG
authors: Birch
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000096:biosynthesis*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009930:Organic Chemicals; D017422:Sequence Analysis, DNA; D017855:Transferases (Other Substituted Phosphate Groups) / Q000235:genetics* / Q000378:metabolism; D014974:Xanthomonas / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D009930:Organic Chemicals; C046156:albicidin; D017855:Transferases (Other Substituted Phosphate Groups); C418187:XabA protein, Xanthomonas albilineans