title: The kinetic and solvent deuterium isotope effects in the 4- and 5-positions of the indole ring on the enzymatic decomposition of L-tryptophan.
abstract: The kinetic and solvent deuterium isotope effects in the 4- and 5-positions of the indole ring on the enzymatic decomposition of l-tryptophan catalysed by the enzyme TPase (EC. 4.1.99.1) were determined. The isotope effects were investigated by the non-competitive method using [4'-(2)H]-l-tryptophan, which was enriched in deuterium in 70% in the 4-position. The numerical values of isotope effects for 100% enrichment in deuterated label in that position were calculated by approximation. Those same isotope effects were determined for [5'-(2)H]-l-tryptophan fully deuteriated in the 5' -position.
authors.affiliation: Department of Chemistry, University of Warsaw, Warsaw, Poland.
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Winnicka
authors.forename: Pawel
authors.initials: P
authors.lastname: Dabrowski
authors.forename: Tomasz
authors.initials: T
authors.lastname: Winek
authors.forename: Marianna
authors.initials: M
authors.lastname: Kanska
mesh_terms: D055162:Biocatalysis; D003903:Deuterium / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry* / Q000378:metabolism*; D007553:Isotope Labeling; D007700:Kinetics; D012997:Solvents / Q000737:chemistry*; D014364:Tryptophan / Q000378:metabolism*; D014368:Tryptophanase / Q000378:metabolism*
chemical_list: D007211:Indoles; D012997:Solvents; C030374:indole; D014364:Tryptophan; D003903:Deuterium; D014368:Tryptophanase