Genome and transcriptome of Papaver somniferum Chinese landrace CHM indicates that massive genome expansion contributes to high benzylisoquinoline alkaloid biosynthesis

Opium poppy(Papaver somniferum)is a source of morphine,codeine,and semisynthetic derivatives,including oxycodone and naltrexone.Here,we report the de novo assembly and genomic analysis of P.somniferum traditional landrace‘Chinese Herbal Medicine’.Variations between the 2.62 Gb CHM genome and that of the previously sequenced high noscapine 1(HN1)variety were also explored.Among 79,668 protein-coding genes,we functionally annotated 88.9%,compared to 68.8%reported in the HN1 genome.Gene family and 4DTv comparative analyses with three other Papaveraceae species revealed that opium poppy underwent two whole-genome duplication(WGD)events.The first of these,in ancestral Ranunculales,expanded gene families related to characteristic secondary metabolite production and disease resistance.The more recent species-specific WGD mediated by transposable elements resulted in massive genome expansion.Genes carrying structural variations and large-effect variants associated with agronomically different phenotypes between CHM and HN1 that were identified through our transcriptomic comparison of multiple organs and developmental stages can enable the development of new varieties.These genomic and transcriptomic analyses will provide a valuable resource that informs future basic and agricultural studies of the opium poppy.

Way to efficient microbial paclitaxel mass production

The microbial synthesis of paclitaxel is attractive for its short-cycle,cost-effectiveness,and sustainability.However,low paclitaxel productivity,depleted capacity during subculture and storage,and unclear biosynthesis mechanisms restrain industrial microbial synthesis.Along with the isolation of various paclitaxel-producing microorganisms and the development of versatile molecular tools,tremendous promises for microbial paclitaxel synthesis have become increasingly prominent.In this review,we summarize the progress of microbial synthesis of paclitaxel in recent years,focusing on paclitaxel-producing endophytes and representative engineering microorganism hosts that were used as chassis for paclitaxel precursor synthesis.Numerous wide-type microbes can manufacture paclitaxel,and fermentation process optimization and strain improvement can greatly enhance the productivity.Engineered microbes can efficiently synthesize precursors of paclitaxel by introducing exogenous synthetic pathway.Mining paclitaxel synthetic pathways and genetic manipulation of endophytes will accelerate the construction of microbial cell factories,indefinitely contributing to paclitaxel mass production by microbes.This review emphasizes the potential and provides solutions for efficient microbial paclitaxel mass production.