Identification of multiple regulatory genes involved in TGase production in Streptomyces mobaraensis DSM 40587  

作　　者：Xian Liu Dan Wang Yuru Zhang Xiaoxin Zhuang Linquan Bai 

机构地区：[1]State Key Laboratory of Microbial Metabolism,School of Life Sciences&Biotechnology,Shanghai Jiao Tong University,Shanghai 200240,China [2]Joint International Research Laboratory of Metabolic&Developmental Sciences,Shanghai Jiao Tong University,Shanghai 200240,China [3]Taixing Dongsheng Bio-Tech Co.,Ltd.,Taixing 225411,China

出　　处：《Engineering Microbiology》2023年第4期20-28,共9页工程微生物学（英文）

基　　金：supported by the National Key R&D Program of China(2021YFC2100600,2019YFA0905400);the Na-tional Natural Science Foundation of China(31830104);Science and Technology Commission of Shanghai Municipality(19430750600,19JC1413000,17JC1403600).

摘　　要：Microbial transglutaminase(TGase)is a protein that is secreted in a mature form and finds wide applications in meat products,tissue scaffold crosslinking,and textile engineering.Streptomyces mobaraensis is the only licensed producer of TGase.However,increasing the production of TGase using metabolic engineering and heterologous expression approaches has encountered challenges in meeting industrial demands.Therefore,it is necessary to identify the regulatory networks involved in TGase biosynthesis to establish a stable and highly efficient TGase cell factory.In this study,we employed a DNA-affinity capture assay and mass spectrometry analysis to discover several transcription factors.Among the candidates,eight were selected and found to impact TGase biosyn-thesis.Notably,SMDS_4150,an AdpA-family regulator,exhibited a significant influence and was hence named AdpASm.Through electrophoretic mobility shift assays,we determined that AdpASm regulates TGase biosynthesis by directly repressing the transcription of tg and indirectly inhibiting the transcription of SMDS_3961.The latter gene encodes a LytR-family positive regulator of TGase biosynthesis.Additionally,AdpASm exhibited negative regulation of its own transcription.To further enhance TGase production,we combined the overexpression of SMDS_3961 with the repression of SMDS_4150,resulting in a remarkable improvement in TGase titer from 28.67 to 52.0 U/mL,representing an 81.37%increase.This study establishes AdpA as a versatile regulator involved in coordinating enzyme biosynthesis in Streptomyces species.Furthermore,we elucidated a cascaded regulatory network governing TGase production.

关 键 词：TRANSGLUTAMINASE Streptomyces mobaraensis AdpA TRANSCRIPTION Regulatory network 

分 类 号：Q93[生物学—微生物学]