? 2014, Eberhardt et al.; licensee Springer.L-citrulline plays an important role in human health and nutrition and is an intermediate of the L-arginine biosynthetic pathway. L-citrulline is a by-product of L-arginine production by Corynebacterium glutamicum. In this study, C. glutamicum was engineered for overproduction of L-citrulline as major product without L-arginine being produced as by-product. To this end, L-arginine biosynthesis was derepressed by deletion of the arginine repressor gene argR and conversion of L-citrulline towards L-arginine was avoided by deletion of the argininosuccinate synthetase gene argG. Moreover, to facilitate L-citrulline production the gene encoding a feedback resistant N-acetyl L-glutamate kinase argBfbr as well as the gene encoding L-ornithine carbamoylphosphate transferase argF were overexpressed. The resulting strain accumulated 44.1 ? 0.5?mM?L-citrulline from glucose minimal medium with a yield of 0.38 ? 0.01?g?g?1 and a volumetric productivity of 0.32 ? 0.01?g?l?1?h?1. In addition, production of L-citrulline from the alternative carbon sources starch, xylose, and glucosamine could be demonstrated.
Eberhardt, D., Jensen, J. V. K., & Wendisch, V. F. (2014). L-citrulline production by metabolically engineered Corynebacterium glutamicum from glucose and alternative carbon sources. AMB Express, 4(1). https://doi.org/10.1186/s13568-014-0085-0