Orphan Pathways for the Biosynthesis of Natural Products in Marine Cyanobacteria

• Applicant: Professor Dr. Harald Groß
• Subject Area: Pharmacy
• Term: from 2004 to 2005
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5442705

The project focuses on the exploration of so-called "orphan pathways" of cyanobacteria. "Orphan pathways" are defined as biosynthetic gene clusters for which the corresponding metabolite is unknown. The marine cyanobacterium Lyngbya majuscula produces structurally unusual and bioactive peptides which are the product of nonribosomal peptide syntheases (NRPSs). Recent genetic analysis revealed the existence of gene clusters encoding NRPS for novel peptidic metabolites, which have not been isolated yet. Using an innovative and interdisciplinary approach, which combines methods of molecular biology an natural products chemistry, this study aims to discover these "orphan molecules". After the expression of the studied gene cluster is demonstrated, the biosynthesis of the corresponding natural product will be tracked using 15N-13C labeled procursors through a series of 15N-13CNMR experiments. With this technique, novel secondary metabolites from cyanobacteria will be accessible. This new strategy for the investigation of "orphan pathways" can also be broadly applied to other organisms with the genetic potential for secondary metabolite biosynthesis.

• DFG Programme: Research Fellowships