Mining and engineering exporters for titer improvement of macrolide biopesticides in Streptomyces

Abstract

Exporter engineering is a promising strategy to construct high-yield Streptomyces for natural product pharmaceuticals in industrial biotechnology. However, available exporters are scarce, due to the limited knowledge of bacterial transporters. Here, we built a workflow for exporter mining and devised a tunable plug-and-play exporter (TuPPE) module to improve the production of macrolide biopesticides in Streptomyces. Combining genome analyses and experimental confirmations, we found three ATPbinding cassette transporters that contribute to milbemycin production in Streptomyces bingchenggensis. We then optimized the expression level of target exporters for milbemycin titer optimization by designing a TuPPE module with replaceable promoters and ribosome binding sites. Finally, broader applications of the TuPPE module were implemented in industrial S. bingchenggensis BC04, Streptomyces avermitilis NEAU12 and Streptomyces cyaneogriseus NMWT1, which led to optimal titer improvement of milbemycin A3/A4, avermectin B 1a and nemadectin a by 24.2%, 53.0% and 41.0%, respectively. Our work provides useful exporters and a convenient TuPPE module for titer improvement of macrolide biopesticides in Streptomyces. More importantly, the feasible exporter mining workflow developed here might shed light on widespread applications of exporter engineering in Streptomyces to boost the production of other secondary metabolites.

Natural nematicidal metabolites and advances in their biocontrol capacity on plant parasitic nematodes

“…This module was implemented in industrial S. avermitilis NEAU12, resulting in a 53% improvement of avermectin B1a production. 202…”

“…This module was implemented in industrial S. avermitilis NEAU12, resulting in a 53% improvement of avermectin B1a production. 202 4.1.3 Biosynthetic gene cluster (BGC) manipulation. In general, the manipulation of biosynthetic gene clusters includes deletion, insertion, point mutation and substitution of genes (or modules), which stimulates the production of specic or new products.…”

Protein Modelling Highlighted Key Catalytic Sites Involved in Position-Specific Glycosylation of Isoflavonoids

“…The heterologous biosynthesis of isoflavonoids faces issues of a low titer and low yield. Following the development of a microbial strain capable of the de novo biosynthesis or biotransformation of an isoflavonoid of interest, efforts, i.e., directed evolution, and engineering of primary metabolism are put forward to improve the final yield [12,17]. It has been reported that the glycosylation of the end-product improves its heterologous biosynthesis rate; therefore, the addition of a UGT gene in the pathway to glycosylate the isoflavonoid of interest is a unique approach to enhance the final yield [18].…”

Comparative Transcriptome-Based Mining of Genes Involved in the Export of Polyether Antibiotics for Titer Improvement

“…Chu et al built a step-by-step workflow based on the TCDB database BLAST, and they included substrate analysis, transporter classification analysis, and phylogenetic analysis to mine BGC-independent exporters. Together with a tunable plug-and-play exporter module with replaceable promoters and ribosome-binding sites, they realized the titer improvement of macrolide biopesticides in different Streptomyces producers [18]. Nevertheless, the current commonly used approaches are mainly sequence-dependent or based on known exporters, and the methods of BGC-independent exporter mining still need development.…”