The Production of Amino Acids by Fermentation Processes

Abstract

This chapter discusses the production of amino acids by fermentation processes. If amino acid is produced in substantial amounts in a medium containing sugars and simple nitrogen compounds by a fermentative procedure, the fermentation might well be called an “amino acid fermentation.’’ Amino acid fermentation is a rapidly expanding branch of industrial fermentation. The result of the survey of amino acid fermentation discussed in the chapter obtained glutamic acid, lysine, ornithine, valine, and alanine. The fermentation mechanism of such an abnormal accumulation of glutamic acid is a very interesting problem from both academic and industrial standpoints. There are two known chemical pathways for L-glutamic acid formation in living organisms, that is, transamination by various transaminases and reductive amination by glutamic acid dehydrogenase. The mechanism of L-glutamic acid formation by reductive amination with L-glutamic acid dehydrogenase is more complicated than that by transamination because, for this reaction to proceed, at least one more dehydrogenase system which will supply the reduced form of coenzyme and a hydrogen-donating substrate are needed.