The present invention relates to a microorganism capable of producing L-lysine and a method for producing L-lysine thereby. More specifically, the present invention relates to a strain possessing resistance to arginine analogues and other analogues besides the characteristics known as necessary for the production of L-lysine, and a method for producing L-lysine comprising culturing the strain in a nutrient culture medium and recovering L-lysine from the culture broth.
L-Lysine, which is one of essential amino acids, has been used as an animal feed supplement because of its ability to improve the quality of feed by increasing the absorption of other amino acids, and used as a food supplement as well. L-Lysine has been used also in medicine, particularly as ingredients of infusion solutions.
L-Lysine can be produced by fermentation using an auxotrophic mutant and/or regulatory mutant, or by enzymatic conversion which comprises treating DL-.alpha.-amino-.beta.-caprolactam (hereinafter referred to as ACL) with L-ACL-hydrolase and ACL-racemase. For commercial production of L-lysine, however, fermentation processes have been more predominantly employed. For example, Japanese Patent Laid-Open No. 82-9797, and Japanese Patent Publication Nos. 82-14839 and 86-35840 disclose the methods using strains having characteristics of vitamin B.sub.1, pantothenic acid and/or biotin requirement for growth; resistance to lysine, threonine and/or isoleucine analogues; resistance to one or more antibiotics e.g. bacitracin, penicillin G and/or polymyxin.