1. Aiba S, Tsunekawa H, Imanaka T (1982) New approach to tryptophan production by Escherichia coli: genetic manipulation of composite plasmids in vitro. Appl Environ Microbiol 43:289?297
2. Hagino H, Nakayama K (1975) l-Tryptophan production by analog-resistant mutants derived from a phenylalanine and tyrosine double auxotroph of Corynebacterium glutamicum. Agric Biol Chem 39:343?349
3. Imanaka T, Tsunekawa H, Aiba S (1980) Phenotypic stability of trp operon recombinant plasmids in Escherichia coli. J Gen Microbiol 118:253?261
4. Katsumata R, Ikeda M, Nakanishi K, Kino K, Kikuchi Y (1989) Construction of tryptophan-hyperproducing strains and lactose-utilizing strains. In: Okada H (ed) Society of Fermentation Technology, Osaka, Japan, p 22
5. Lowry OH, Rosebrough NH, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193:265?273