Biosyntesis of L-Lysin from Methanol

This project was initiated in 2001 in colaboration with SINTEF Applied Biotechnology and the BioTechnology Institute at the University of Minnesota. L-Lysine is an essential amino acid widely used as an additive in food and feed, and the global L-Lysine market is large and growing. Today, commercial L-Lysine production is made fermentative by
using bacteria growing on sugars as carbon and energy source. However, the need for new and better production processes is emerging, and in particular the possibility to utilize alternative carbon sources has both economical and ecological advantages. One-carbon (C1)-compounds such as methanol are highly interesting in this regard, due to low price, high abundance and high purity. The unusual metabolic capabilities of thermotolerant methylotrophic bacteria make them interesting candidates for the bioproduction of amino acids, as well as recombinant proteins, vitamins, coenzymes, and cytochromes. The Gram-positive bacterium Bacillus methanolicus can produce high levels
(55 g/l) of glutamate at 50oC using methanol as a carbon source in fed-batch fermentations, and by classical mutagenesis a B. methanolicus mutant secreting 35 g/l of L-Lysine has been made at the University of Minnesota. Our goal in this project is to develop and apply recombinant DNA technology to make B. methanolicus mutants producing L-Lysine at industrial competitive levels.

Key Papers

Brautaset, T., Williams, M.D., Dillingham, R.D., Kaufmann, C., Bennaars, A., Crabbe, E., and Flickinger, M.C. (2003). The role of the Bacillus methanolicus citrate synthase synthase II gene, citY, in regulating the secretion of glutamate in L-lysine secreting mutants. Applied and Environmental Microbiology 69: 3986-3995.

Brautaset T, Jakobsen M O, Flickinger MC, Valla S, Ellingsen TE. (2004). Plasmid-Dependent Methylotrophy in Thermotolerant Bacillus methanolicus. J Bacteriol. Mar 1;186(5):1229-1238.

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Biopolymers
Bioprospecting of marine microorganisms
Engineered antibiotic synthesis
Gene Expression
Osmoregulation
Metabolic Engineering