Albicidin Pathotoxin Produced byXanthomonas albilineansIs Encoded by Three Large PKS and NRPS Genes Present in a Gene Cluster Also Containing Several Putative Modifying, Regulatory, and Resistance Genes

• DOI: 10.1094/mpmi.2004.17.4.414
• Publication Date: 2007-05-11T09:29:55Z
• Authors: Monique Royer; Laurent Costet; Eric Vivien; Martine Bes; Arnaud Cousin; Anne Damais; Isabelle Pieretti; Alexandre Savin; Sandrine Megessier; Magali Viard; Roger Frutos; Dean W. Gabriel; Philippe C. Rott
• Keywords: Gene cluster; Nonribosomal peptide; Xanthomonas; Polyketide synthase

Xanthomonas albilineans, which causes leaf scald disease of sugarcane, produces a highly potent pathotoxin called albicidin. We report here sequencing and homology analysis the major gene cluster, XALB1 (55,839 bp), second, smaller region, XALB2 (2,986 involved in albicidin biosynthesis. contains 20 open reading frames, including i) three large genes with modular architecture characteristic polyketide synthases (PKSs) nonribosomal peptide (NRPSs) ii) several putative modifying, regulatory, resistance genes. Sequencing complementation studies six albicidin-defective mutants enabled us to confirm involvement PKS NRPS encoded by production. only one that is required for post-translational activation enzymes, confirming these enzymes In silico or allowed propose model backbone assembly gain insight into structural features this pathotoxin. This first description complete mixed PKS—NRPS cluster toxin production genus Xanthomonas.