Turnover Is Rate-Limited by Deglycosylation for Micromonospora viridifaciens Sialidase-Catalyzed Hydrolyses: Conformational Implications for the Michaelis Complex
作者:Jefferson Chan、April Lu、Andrew J. Bennet
DOI:10.1021/ja109199p
日期:2011.3.9
effects (KIEs) on k(cat) for the ring oxygen ((18)V), leaving group oxygen ((18)V), anomeric carbon ((13)V), C3-carbon ((13)V), C3-R deuterium ((D)V(R)), C3-S deuterium ((D)V(S)), and C3-dideuterium ((D)(2)V) are 0.986 ± 0.003, 1.003 ± 0.005, 1.021 ± 0.006, 1.001 ± 0.008, 1.029 ± 0.007, 0.891 ± 0.008, and 0.890 ± 0.006, respectively. The solvent deuterium KIE ((D(2)O)V) for the sialidase-catalyzed hydrolysis
基于核心结构 7-(5-acetamido-3,5-dideoxy-d-glycero-α-d-galacto-non-2-ulopyranosylonic acid)-(2→6) 的一组七种同位素取代的唾液酸苷天然底物类似物)-β-D-吡喃半乳糖氧基)-8-氟-4-甲基香豆素 (1, Neu5Acα2,6GalβFMU) 已被合成并用于探测 M. viridifaciens 唾液酸酶转换的限速步骤。环氧 ((18)V)、离去基团氧 ((18)V)、异头碳 ((13)V)、C3-碳 ((13) V)、C3-R 氘 ((D)V(R))、C3-S 氘 ((D)V(S)) 和 C3-双氘 ((D)(2)V) 为 0.986 ± 0.003、1.003分别为 ± 0.005、1.021 ± 0.006、1.001 ± 0.008、1.029 ± 0.007、0.891 ± 0.008 和 0.890