Synthetic Biological Platform of Corynebrick Vectors and Its Application to Improve Xylose Utilization and Cell Growth in Corynebacterium Glutamicum

Metabolic engineered Corynebacterium glutamicum, the non-pathogenic microorganism, is widely contributes to the industrial production of amino acid. To broaden its utilization of metabolic engineering in C. glutamicum, we established a synthetic biology platform vector, called CoryneBrick vector, which can be used as an expression vector in C. glutamicum and as an E. coli-C. glutamicum shuttle vector. For application of the CoryneBrick vector, we constructed the xylose utilization pathway encoding the xylA and xylB in the xylose-negative C. glutamicum wild type by rapid BglBrick cloning method, resulting in a growth rate of 0.11 ± 0.004 h^-1 and a xylose uptake rate of 3.35 mmol/gDW/h when 1% xylose was used as sole carbon source. Also, we applied the CoryneBrick vector with a conventional C. glutamicum expression vector for two-plasmid expression systems. Using this two-plasmid expression system, we improved xylose utilization of C. glutamicum not only introducing the xylose utilization pathway but overexpressing the pentose phosphate pathway genes tal, gnd, or the phosphoketolase gene xpkA, resulting increased the growth rates and xylose uptake rates compared to the wild-type with xylose utilization pathway alone. Thus, this study could be useful for metabolic engineering of C. glutamicum to produce amino acid and other high valued chemicals. This work was supported by the BK21 plus program through the National Research Foundation (NRF) funded by the Ministry of Education of Korea.

Reference

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[2] Jo, S., Yoon, J., Lee, S.M., Um, Y., Han, S.O., *Woo, H.M., Modular pathway engineering of Corynebacterium glutamicum to improve xylose utilization and succinate production (2017) J. Biotechnol.