A chromatogram-simplified Streptomyces albus host for heterologous production of natural products

Abstract

Cloning natural product biosynthetic gene clusters from cultured or uncultured sources and their subsequent expression by genetically tractable heterologous hosts is an essential strategy for the elucidation and characterisation of novel microbial natural products. The availability of suitable expression hosts is a critical aspect of this workflow. In this work, we mutagenised five endogenous biosynthetic gene clusters from Streptomyces albus S4, which reduced the complexity of chemical extracts generated from the strain and eliminated antifungal and antibacterial bioactivity. We showed that the resulting quintuple mutant can express foreign biosynthetic gene clusters by heterologously producing actinorhodin, cinnamycin and prunustatin. We envisage that our strain will be a useful addition to the growing suite of heterologous expression hosts available for exploring microbial secondary metabolism. Keywords Streptomyces Á Streptomyces albus Á Secondary metabolites Á Natural products Á Heterologous expression Asif Fazal and Divya Thankachan have contributed equally to this work.

The Application of Regulatory Cascades in Streptomyces: Yield Enhancement and Metabolite Mining

“…There are series of reviews on this aspect. Also some heterologous expression was solved with overexpression of regulatory genes by proper promoters in the target clusters (Fazal et al, 2019;Myronovskyi and Luzhetskyy, 2019;Nepal and Wang, 2019;Xu and Wright, 2019).…”

De novo biosynthesis of garbanzol and fustin in Streptomyces albus based on a potential flavanone 3‐hydroxylase with 2‐hydroxylase side activity

“…The strain S. albus J1074 has been widely used as a workhorse for heterologous production of a wide range of natural products over the last two decades (Lombó et al ., 2006; Myronovskyi et al ., 2016; Liu et al ., 2018; Fazal et al ., 2020) and could be regarded as a promising platform for heterologous flavonoid expression, but multiple genome improvements are needed. Firstly, improvements focused on increasing the intracellular availability of the main bottleneck in flavonoid biosynthesis (malonyl‐CoA) would be necessary (Takamura and Nomura, 1988; Kurth et al ., 2009; Santos et al ., 2011), as well as limiting its use by other native biosynthetic clusters (Myronovskyi et al ., 2018).…”

Recent Advances in the Heterologous Biosynthesis of Natural Products from Streptomyces

“…Streptomyces host strains were engineered by deleting or repressing the expression of unwanted BGCs, and the resulting engineered strains were employed as hosts for the integration of heterologous BGCs, leading to the production of the target products [103]. Several methods are available to develop clean hosts, such as a PCR-targeted system [104], site-specific recombination using Cre-loxP [105,106], meganuclease I-SceI [107], and clustered regularly interspaced short palindromic repeat (CRISPR)/Cas genome editing tools [108]. A PCR-targeted system is a useful tool for gene knockout.…”