Scholarlink

Abstract <p>Climate change–associated abiotic stresses threaten agricultural productivity, creating a need for sustainable strategies that improve plant resilience. Pteridic acids F and H (PTA-F and PTA-H), originally isolated from <i>Streptomyces iranensis</i> HM 35, are plant growth–promoting polyketides with reported activity under drought and salinity stress. However, reported production was extremely low (~ 0.08 and 0.02&#xa0;mg/L), limiting further development and application. Here, we established a heterologous production platform for PTA biosynthesis by cloning the 68-kb type I polyketide synthase biosynthetic gene cluster using Cas12a-assisted precise targeted cloning using in vivo Cre-lox recombination (CAPTURE), followed by CRISPR-Cas9-mediated genomic integration and promoter engineering in <i>Streptomyces</i> hosts. Initial heterologous expression resulted in detectable elaiophylin production but not PTA, whereas BGC engineering with the strong constitutive <i>kasO</i>p* promoter enabled PTA production (although&#xa0;below&#xa0;the limit of quantification). Genome-scale metabolic model–guided media optimization further improved production and fed-batch fermentation yielded 1.7&#xa0;mg/L PTA in J1074-PTA-<i>kasO</i>p* and 2.8&#xa0;mg/L PTA in NBC1270-PTA-<i>kasO</i>p*. These titers represent a&#xa0;more tha n 20-fold increase compared with the native producer under comparable conditions. This work provides the first functional heterologous platform for PTA biosynthesis and demonstrates how synthetic biology and genome-scale metabolic modeling can be combined to improve production of complex plant-beneficial polyketides.</p> Key points <p>• <i>Direct BGC cloning and engineering enabled production of PTA in heterologous host.</i></p> <p>• <i>Genome-scale metabolic models (GEMs) guided media optimization for PTA production.</i></p> <p>• <i>Fed-batch fermentation achieved</i> &gt; <i>20-fold PTA titer improvement over native strain.</i></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Heterologous production of a plant biostimulant in Streptomyces albidoflavus

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年6月20日

查看全文
  • Renata Sigrist,
  • Te Chen,
  • Marta Reventós Montané,
  • Peter Gockel,
  • Yijun Qiao,
  • Mathias Jönsson,
  • Zhijie Yang,
  • Tilmann Weber,
  • Ling Ding,
  • Emre Özdemir,
  • Lei Yang

摘要

Abstract

Climate change–associated abiotic stresses threaten agricultural productivity, creating a need for sustainable strategies that improve plant resilience. Pteridic acids F and H (PTA-F and PTA-H), originally isolated from Streptomyces iranensis HM 35, are plant growth–promoting polyketides with reported activity under drought and salinity stress. However, reported production was extremely low (~ 0.08 and 0.02 mg/L), limiting further development and application. Here, we established a heterologous production platform for PTA biosynthesis by cloning the 68-kb type I polyketide synthase biosynthetic gene cluster using Cas12a-assisted precise targeted cloning using in vivo Cre-lox recombination (CAPTURE), followed by CRISPR-Cas9-mediated genomic integration and promoter engineering in Streptomyces hosts. Initial heterologous expression resulted in detectable elaiophylin production but not PTA, whereas BGC engineering with the strong constitutive kasOp* promoter enabled PTA production (although below the limit of quantification). Genome-scale metabolic model–guided media optimization further improved production and fed-batch fermentation yielded 1.7 mg/L PTA in J1074-PTA-kasOp* and 2.8 mg/L PTA in NBC1270-PTA-kasOp*. These titers represent a more tha n 20-fold increase compared with the native producer under comparable conditions. This work provides the first functional heterologous platform for PTA biosynthesis and demonstrates how synthetic biology and genome-scale metabolic modeling can be combined to improve production of complex plant-beneficial polyketides.

Key points

• Direct BGC cloning and engineering enabled production of PTA in heterologous host.

• Genome-scale metabolic models (GEMs) guided media optimization for PTA production.

• Fed-batch fermentation achieved > 20-fold PTA titer improvement over native strain.