Bang W G, Lang S, Sahm H, Wagner F
Institute of Biochemistry and Biotechnology, Technical University Braunschweig, Mascheroder Weg 1, D-3300 Braunschweig, W. Germany.
Biotechnol Bioeng. 1983 Apr;25(4):999-1011. doi: 10.1002/bit.260250410.
Whole cells of Escherichia coli B 10 having high tryptophan synthetase activity were used directly as an enzyme source to produce L-tryptophan from indole and L- or D,L-serine. This strain is tryptophan auxotrophic, which is tryptophanase negative and, in addition, L- and D-serine deaminase negative under production conditions. To avoid inhibition of tryptophan synthetase by a high concentration of indole, nonaqueous organic solvents, Amberlite XAD-2 adsorbent, and nonionic detergents were used as reservoirs of indole in the reaction mixture for the production of L-tryptophan. As a result, different effects were observed on the production of L-tryptophan. Particularly, among the nonionic detergents, Triton X-100 was very efficient. Using Triton X-100 for production of L-tryptophan from indole and L- or D,L-serine by whole cells of Escherichia coli B 10, 14.14 g/100 mL and 14.2 g/100 mL of L-tryptophan were produced at 37 degrees C for 60 h.
具有高色氨酸合成酶活性的大肠杆菌B 10全细胞被直接用作酶源，从吲哚和L-或D,L-丝氨酸生产L-色氨酸。该菌株是色氨酸营养缺陷型，色氨酸酶阴性，此外，在生产条件下L-和D-丝氨酸脱氨酶也阴性。为避免高浓度吲哚对色氨酸合成酶的抑制，非水有机溶剂、Amberlite XAD-2吸附剂和非离子洗涤剂被用作反应混合物中吲哚的储存库，用于生产L-色氨酸。结果，观察到对L-色氨酸生产有不同的影响。特别是，在非离子洗涤剂中，Triton X-100非常有效。使用Triton X-100通过大肠杆菌B 10全细胞从吲哚和L-或D,L-丝氨酸生产L-色氨酸，在37℃下反应60小时，可产生14.14 g/100 mL和14.2 g/100 mL的L-色氨酸。
