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A semi-synthesis platform for efficient production and exploration of didemnin-based drugs

ABSTRACT: In this study, we report the screening of the yield of didemnin B from 18 Tistrella strains we collected from different regions worldwide. Among them, one T. mobilis strain was further investigated due to its capability to produce the highest yield of didemnin B in a fermentation medium. To improve the productivity of the chosen strain, we performed 11 rounds of random mutagenesis/screening and optimised culture conditions. The resultant mutated strain produced over 500 mg/L of didemnin B in a 50-L fermentation tank. We further tested the strain in an industrial-scale fermentation tank (4,000-L), resulting in the production of didemnin B approximately 480 mg/L. Furthermore, we developed two simple and efficient chemical strategies for converting didemnin B to plitidepsin. One of the strategies involves a one-step synthetic route with over 90% overall yield. The modifications in the hydroxyl group of iso-statine (iso-Sta–OH) in didemnin B can greatly impact on its bioactivity. Therefore, we further synthesised 13 new didemnin B derivatives with modifications in iso-Sta–OH for studying the structure–activity relationships. In addition, 3 photo-affinity-based didemnin probes, bearing diazirine and alkyne groups, were prepared and employed in proteomic profiling studies, which allowed the deduction of binding proteins in the THP-1 cell line. Overall, our platform not only provides a practical and sustainable solution for producing the drug molecule plitidepsin, but also offers the opportunities to utilise the functions of didemnin derivatives. We envision that our platform can expedite the development of didemnin-based drugs.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Yun Ge

LAB HEAD: Yun Ge

PROVIDER: PXD046155 | Pride | 2024-02-13

REPOSITORIES: Pride

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Project description:The most widely-used method for detecting and measuring genome-wide protein-DNA interactions is chromatin immunoprecipitation on tiling microarrays, commonly known as ChIP-chip. Many tiling array platforms, amplification methods, and analysis algorithms exist for ChIP-chip, but a rigorous assessment of the relative performance of these factors has not been reported. In a multi-lab simulation of a ChIP-chip experiment, we conducted the first objective analysis of tiling array platforms and analysis algorithms. We designed a complex mixture of human genomic DNA with a "spike-in" comprised of nearly 100 human sequences at various concentrations. Eight independent groups hybridized these mixtures to four different tiling array platforms. The groups were blind to the composition of the spike-in mix, the range of concentrations covered, or how many sequences it contained. 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A semi-synthesis platform for efficient production and exploration of didemnin-based drugs

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