PRODUÇÃO DE AMINOÁCIDOS A PARTIR DE SACAROSE EM CORYNEBACTERIUM GLUTAMICUM

摘要

Methods and compositions for increased production of amino acids from C. glutamicum using sucrose as a carbon source are described. In one aspect, increased production of L-lysine from C. glutamicum is accomplished by using a strain having a mutation in the ptsF gene encoding fructose-PTS enzyme that attenuates or blocks fructose import into the cell when such strain is grown on media containing sucrose as a carbon source and production is increased by providing glucose isomerase in the fermentation media. The glucose isomerase may be exogenously added or expressed in the strain and exported into the media. In certain embodiments the media also contain an invertase. In another aspect increased production of L-lysine is accomplished by making a C. glutamicum strain having the ptsF mutation and a second mutation in a fructose exporter function. The dual mutation retains imported fructose in the cell. In certain embodiments, the strain also overexpresses at least one of a glucose isomerase and glucokinase activity in the cell to drive imported fructose toward the pentose phosphate pathway to increase L-lysine production.