文献类型：期刊文献

英文题名：Enhanced heparosan biosynthesis in Corynebacterium glutamicum by systematic metabolic engineering and translation-level fine-tuning

作者：Zhang, Jie[1];Cui, Yanan[1];Zhang, Peiyi[1];Zhao, Mengqi[1];Fan, Liqiang[1];Li, Xu[1];Deng, Chen[1];Zhao, Liming[1,2]

机构：[1]East China Univ Sci & Technol, Sch Biotechnol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Shanghai Collaborat Innovat Ctr Biomfg Technol SCI, Shanghai 200237, Peoples R China

年份：2026

卷号：13

期号：1

外文期刊名：BIORESOURCES AND BIOPROCESSING

收录：;EI(收录号：20263421329526);Scopus(收录号：2-s2.0-105047535707);WOS:【SCI-EXPANDED(收录号:WOS:001850495700001)】；

基金：This work was financially supported by the National Natural Science Foundation of China (32301214), Fundamental and Interdisciplinary Disciplines Breakthrough Plan of the Ministry of Education of China (JYB2025XDXM509).

语种：英文

外文关键词：Heparosan; Corynebacterium glutamicum; Systematic metabolic engineering; Translation-level fine-tuning; Fed-batch fermentation

摘要：As a widely used anticoagulant, heparin is industrially produced chiefly via animal tissue extraction, which suffers from unstable supply and potential safety hazards. Heparosan shares a similar polysaccharide backbone with heparin and can be converted into heparin under mild enzymatic catalysis. In addition, heparosan exhibits favorable biocompatibility and non-immunogenicity, rendering its efficient, eco-friendly biosynthesis essential. In this study, we systematically engineered Corynebacterium glutamicum, a Generally Recognized as Safe (GRAS) microorganism, to synthesize heparosan via two complementary strategies. First, genome-scale modification was implemented to stably upregulate genes ugd, glmS, and ndk. The heparosan titer of recombinant strain Cg24 increased from 226.37 to 595.39 mg/L. Second, translation-level fine-tuning was implemented to modulate expression of individual genes within the kfiB-kfiC-kfiA cassette by constructing a high-coverage random ribosome binding site (RBS) library, which further lifted heparosan titer to 1161.37 mg/L. In fed-batch fermentation using a 5 L bioreactor with a two-stage growth-production regulation strategy, the recombinant strain Cg24-11 produced 5.36 g/L of heparosan, demonstrating its great potential for efficient heparosan biosynthesis. This combined modification strategy also provides valuable references for constructing high-efficiency cell factories for other complex compounds.