Heterologous Expression of Epoxomicin in .

Epoxomicin is an epoxyketone proteasome inhibitor with synthetic derivatives approved or under investigation for treatment of multiple myeloma. To leverage the advantages of as a rapidly growing and readily engineered host for the production of epoxomicin and analogues, we expressed codon-optimized versions of the epoxomicin biosynthetic genes, , and . Epoxomicin was detected, but the major product was a ketone resulting from α,β-keto acid precursor decarboxylation.

Metagenomic domain substitution for the high-throughput modification of nonribosomal peptides.

The modular nature of nonribosomal peptide biosynthesis has driven efforts to generate peptide analogs by substituting amino acid-specifying domains within nonribosomal peptide synthetase (NRPS) enzymes. Rational NRPS engineering has increasingly focused on finding evolutionarily favored recombination sites for domain substitution. Here we present an alternative evolution-inspired approach that involves large-scale diversification and screening.