Development of tailor-made secretion platform for the enhanced production of recombinant protein in Corynebacterium glutamicum

Abstract

Corynebacterium glutamicum is generally recognize as a safe strain that is used for mass production of various substances such as amino acids and nucleic acids and is an important industrial microorganism that is used in the industrial field after authorization, for the first time in Korea, as a genetically modified microorganism that produces recombinant proteins. In addition, the secretion production system industrial strain of C. glutamicum is highly valuable because it enables the economical production of recombinant proteins. However, limitations of strain engineering and expression systems to produce recombinant proteins in C. glutamicum still exist. In particular, the system for secretion production, which is advantageous industrially, has limitations in its application because its secretion effectiveness varies depending on the type of target protein. Therefore, in this study, a high expression system for a recombinant protein of C. glutamicum was constructed, and a synthetic signal peptide library was constructed to develop a secretion production system with improved secretion efficiency compared to that of the existing secretion signal system. In addition, a method using a microfluidic device was introduced for high-throughput screening that can quickly and efficiently find a secretion production system optimized for a target product using the developed synthetic signal peptide library. Using this, it was confirmed that a new synthetic signal peptide combination could be screened to engineer the C. glutamicum to be efficient in secretion production. The transcriptional analysis method was used to search for factors that change during secretion. Using this strategy, a more efficient secretory system was developed. In this study, the development of various secretion platforms for high production of recombinant proteins using C. glutamicum is described, and thus, the world's highest secretion titer was finally secured in C. glutamicum.