RECENT ADVANCES IN THE PHYSIOLOGY AND GENETICS OF AMINO ACID-PRODUCING BACTERIA

Corynebacterium glutamicum and its close relatives, C. flavum and C. l actofermentum, have been used for over 3 decades in the industrial pro duction of amino acids by fermentation. Since 1984, several research g roups have started programs to develop metabolic engineering principle s for amino acid-producing Corynebacterium strains. Initially, the pro grams concentrated on the isolation of genes encoding (deregulated) bi osynthetic enzymes and the development of general molecular biology to ols such as cloning vectors and DNA transfer methods. With most of the genes and tools now available, recombinant DNA technology can be appl ied in strain improvement. To accomplish these improvements, it is cri tical and advantageous to understand the mechanisms of gene expression and regulation as well as the biochemistry and physiology of the spec ies being engineered. This review explores the advances made in the un derstanding and application of amino acid-producing bacteria in the ea rly 1990s.