Metabolic Systems Engineering Approach for Efficient Microbial Fermentation and Future Perspectives

摘要

The recent advancement on metabolic systems engineering was reviewed based on our recent research results in terms of metabolic signal flow diagram approach, metabolic flux analysis (MFA) in particular with isotopomer distribution using NMR and/or GC-MS, synthesis and optimization of metabolic flux distribution (MFD), modification of MFD by gene manipulation and by controlling culture environment, metabolic control analysis (MCA), design of metabolic regulation structure, and, identification of unknown pathways with isotope tracing by NMR. The main characteristics of metabolic engineering is to treat metabolism as a network or entirety instead of individual reactions. The applications were made for poly-3-hydroxybutyrate (PHB) production using Ralstonia eutropha and recombinant Escherichia coli, lactate production by recombinant Saccharomyces cerevisiae, pyruvate production by vitamin auxotrophic yeast Toluropsis glabrata, lysine production using Corynebacterium glutamicum, and energetic analysis of photosynthesic microorganisms. The characteristics of each approach were reviewed with their applications. It is becoming important to study gene and protein expressions in relation to metabolic regulations.