Genetika Articles The Threonine Story

The Threonine Story

The Threonine Story
Vladimir G. Debabov
State Research Institute of Genetics and Selection of Industrial Microorganisms,
1st Dorozhnyi proezd,Moscow 113545, Russia. E-mail: boss@genetika.ru
L-Threonine is an essential amino acid which has recently been brought into agricultural industry
for balancing the livestock feed. l-Threonine is produced by microbial synthesis using
glucose or sucrose as substrates. For the process to be cost-effective, the microbial strain must
be capable of threonine overproduction. This paper reviews the biochemical pathways of lthreonine
synthesis in bacteria and the regulation of these pathways, the principles and the
techniques of constructing high-producing strains, and the most efficient strains thus developed.
Keywords. l-Threonine, Bacterial biosynthesis, Breakdown, Transport, Regulation, Highproducing
strains
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
2 Metabolism of L-Threonine and its Regulation in Escherichia coli 114
2.1 Biosynthesis of l-Threonine and its Regulation . . . . . . . . . . 114
2.2 Breakdown of l-Threonine . . . . . . . . . . . . . . . . . . . . . . 117
2.3 Transport of l-Threonine into and out of the Cell . . . . . . . . . 117
3 General Requirements for Industrial Producing Strains . . . . . 120
4 Creation ofL-Threonine Producers . . . . . . . . . . . . . . . . . 120
4.1 Escherichia coli Strains . . . . . . . . . . . . . . . . . . . . . . . . 121
4.2 Other Enterobacteriaceae . . . . . . . . . . . . . . . . . . . . . . 127
4.3 Corynebacterium glutamicum . . . . . . . . . . . . . . . . . . . . 128
4.4 Alcohol-Utilizing Bacteria . . . . . . . . . . . . . . . . . . . . . . 131
5 Conclusions and Prospects . . . . . . . . . . . . . . . . . . . . . 132
6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
CHAPTER 1
Advances in

The Threonine Story

Vladimir G. Debabov

State Research Institute of Genetics and Selection of Industrial Microorganisms,

1st Dorozhnyi proezd,Moscow 113545, Russia. E-mail: boss@genetika.ru

L-Threonine is an essential amino acid which has recently been brought into agricultural industry for balancing the livestock feed. l-Threonine is produced by microbial synthesis using glucose or sucrose as substrates. For the process to be cost-effective, the microbial strain must be capable of threonine overproduction. This paper reviews the biochemical pathways of lthreonine synthesis in bacteria and the regulation of these pathways, the principles and the techniques of constructing high-producing strains, and the most efficient strains thus developed.

Keywords. l-Threonine, Bacterial biosynthesis, Breakdown, Transport, Regulation, Highproducing strains

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

2 Metabolism of L-Threonine and its Regulation in Escherichia coli 114

2.1 Biosynthesis of l-Threonine and its Regulation . . . . . . . . . . 114

2.2 Breakdown of l-Threonine . . . . . . . . . . . . . . . . . . . . . . 117

2.3 Transport of l-Threonine into and out of the Cell . . . . . . . . . 117

3 General Requirements for Industrial Producing Strains . . . . . 120

4 Creation ofL-Threonine Producers . . . . . . . . . . . . . . . . . 120

4.1 Escherichia coli Strains . . . . . . . . . . . . . . . . . . . . . . . . 121

4.2 Other Enterobacteriaceae . . . . . . . . . . . . . . . . . . . . . . 127

4.3 Corynebacterium glutamicum . . . . . . . . . . . . . . . . . . . . 128

4.4 Alcohol-Utilizing Bacteria . . . . . . . . . . . . . . . . . . . . . . 131

5 Conclusions and Prospects . . . . . . . . . . . . . . . . . . . . . 132

6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

CHAPTER 1

Advances in

05.01.2003, 4316 просмотров.