@article{oai:tsukuba.repo.nii.ac.jp:00025870,
 author = {島田, 秋彦 and Shimada, Akihiko and Ozaki, Haruka and Saito, Takeshi and Fujii, Noriko},
 issue = {29},
 journal = {Journal of chromatography. B, Analytical technologies in the biomedical and life sciences},
 month = {Nov},
 note = {Tryptophanase, L-tryptophan indole-lyase with extremely absolute stereospecificity, can change the stereospecificity in concentrated diammonium hydrogenphosphate solution. While tryptophanase is not inert to d-serine in the absence of diammonium hydrogenphosphate, it can undergo L-tryptophan synthesis from d-serine along with indole in the presence of it. It has been well known that tryptophanase synthesizes L-tryptophan from l-serine through a β-substitution mechanism of the ping-pong type. However, a metabolic pathway of L-tryptophan synthesis from d-serine has remained unclear. The present study aims to elucidate it. Diammonium hydrogenphosphate plays a role in the emergence of catalytic activity on d-serine. The salt gives tryptophanase a small conformational change, which makes it possible to catalyze d-serine. Tryptophanase-bound d-serine produces L-tryptophan synthesis by β-replacement reaction via the enzyme-bound aminoacrylate intermediate. Our result will be valuable in studying the origin of homochirality.},
 pages = {3289--3295},
 title = {Reaction pathway of tryptophanase-catalyzed L-tryptophan synthesis from D-serine},
 volume = {879},
 year = {2011}
}