title: Production of a novel tryptophan analog, beta-1-indazole-L-alanine with tryptophan synthase of Escherichia coli.
abstract: The tryptophan synthase alpha 2 beta 2 complex from Escherichia coli has been found to catalyze the beta-replacement reaction of L-serine with indazole, an indole analog which has a nitrogen atom at the 2-position (pyrazole ring). The reaction product was isolated and identified as beta-indazolealanine by mass spectrometric, elemental and NMR analyses. Careful assignment of 1H- and 13C-signals with several NMR techniques revealed that the beta-carbon of the product alanine moiety was bound to the 1-N-position of the indazole ring. This is the first example of the beta-replacement reaction catalyzed by tryptophan synthase occurring at any other position than the 3-position of indole analogs.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004926:Escherichia coli / Q000201:enzymology*; D007191:Indazoles / Q000096:biosynthesis*; D009682:Magnetic Resonance Spectroscopy; D011720:Pyrazoles / Q000096:biosynthesis*; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000096:biosynthesis; D014367:Tryptophan Synthase / Q000378:metabolism*
chemical_list: D007191:Indazoles; D011720:Pyrazoles; C047992:beta-1-indazolealanine; D014364:Tryptophan; D014367:Tryptophan Synthase