Metabolic glutamic acid fermentation

Glutamic Acid Fermentation Discovery of Glutamic Acid-Producing Microorganisms, Analysis of the Production Mechanism, Metabolic Engineering, and Industrial Production Process... 

This chapter provides an overview of the establishment of glutamic acid fermentation and summarizes the molecular mechanism of glutamic acid production by C glutamicum. Moreover, it provides a discussion of metabolic engineering of C utamicum for glutamic acid production, as well as glutamic acid production by other microorganisms. 

As with glutamic acid production, some modification of the normal metabolic pathway of C. glutamicum imposed by the fermentation conditions, is necessary in order to accumulate lysine in the medium. At present, worldwide production of L-lysine by fermentation routes totals some 70,000 tonnes annually, about 40% of this by Japan. About 9,000 tonnes of racemic lysine (DL mixture) per year is also produced synthetically from petrochemical sources. One interesting synthetic substrate for DL-lysine is caprolactam (or 6-amino-caproic acid), a starting material, which is readily available on a tonnage scale from its use as a nylon monomer. 

Vuoristo, K.S., Mars, A.E., Sangra, J.V., Springer, J. et al. (2015) Metabolic engineering of the mixed-acid fermentation pathway of Escherichia coli for anaerobic production of glutamate and itaconate. AAIB Express, 5, 61. 

In the analysis of fermentation processes, the production of the concentration of cell and metabolic products formed in the fermentor can be accomplished by the technique of material balance [1]. For example, the stoichiometry of the fermentation of the microorganism Brevibacterium flavum, which produces glutamic acid, may be represented by the following two chemical reactions ... 

Figure 14.2. Example of some metabolic pathways adopted by Lactobacillus plantarum during fermentation of vegetable and fruit juices. He, isoleucine Leu, leucine Val, valine His, histidine Glu, glutamic acid BcAT, branched-chain aminotransferase KDC, a-keto acid decarboxylase ADH, alcohol dehydrogenase MLE, malol-actlc enzyme HDC, histidine decarboxylase (Adapted from Filannino etal. 2014)...

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