Comprehensive screening of industrially relevant components at genome scale using a high-quality gene overexpression collection of Corynebacterium glutamicum.

Abstract

Development of efficient microbial strains for biomanufacturing requires deep understanding of the biology and functional components responsible for the synthesis, transport, and tolerance of the target compounds. A high-quality controllable gene overexpression strain collection was constructed for the industrial workhorse Corynebacterium glutamicum covering 99.7% of its genes. The collection was then used for comprehensive screening of components relevant to biomanufacturing features. In total, 15 components endowing cells with improved hyperosmotic tolerance and l-lysine productivity were identified, including novel transcriptional factors and DNA repair proteins. Systematic interrogation of a subset of the collection revealed efficient and specific exporters functioning in both C. glutamicum and Escherichia coli. Application of the new exporters was showcased to construct a strain with the highest l-threonine production level reported for C. glutamicum (75.1 g/l and 1.5 g/l·h) thus far. The genome-scale gene overexpression collection will serve as a valuable resource for fundamental biological studies and for developing industrial microorganisms for producing amino acids and other biochemicals.