Figure 3.
Orthogonal Active Site Identification System (OASIS) for proteomic identification and study of PKS and NRPS enzymes. Natural product producer proteomes are enriched with domain-specific probes (RG = protein reactive group), followed by MudPIT MS analysis. The collection of multiple datasets using orthogonal probes allows specific identification of modular biosynthetic enzymes, which contain multiple active sites on a single polypeptide. The application of orthogonal probes can also be used to facilitate study of specific subsets of natural product biosynthetic enzymes.