title: Kinetic mechanism of fuculose-1-phosphate aldolase from the hyperthermophilic archaeon Methanococcus jannaschii.
abstract: Fuculose-1-phosphate aldolase (FucA) is a useful biocatalyst with potential applications in chiral synthesis. In this study, the overall kinetic mechanism of FucA from the archaeon Methanococcus jannaschii was studied. The K(m) values of dihydroxyacetone phosphate (DHAP) and dl-glyceraldehyde were 0.09 and 0.74 mM, respectively. Dead-end inhibition by trimethyl phosphonoacetate and dl-threose were competitive and uncompetitive with respect to DHAP and dl-glyceraldehyde. Inhibition patterns obtained using reaction products were noncompetitive vs. DHAP and competitive vs. dl-glyceraldehyde. The equilibrium constant was 8.309×10(-3) M as assessed by varying the [DHAP]/[product] ratio at a fixed dl-glyceraldehyde concentration and by measuring the change in DHAP concentration after equilibrium was reached. This constant is consistent with the K(eq) value obtained from (13)C NMR (15.625×10(-3) M). The resultant inhibition kinetics may suggest the insights of kinetic mechanism of the FucA catalyzed reaction.
authors.affiliation: Department of Chemistry and Research Institute of Natural Sciences, Hanyang University, Seoul 133-791, Republic of Korea.
authors.forename: Hae-Chul
authors.initials: HC
authors.lastname: Park
authors.forename: Joon-Shik
authors.initials: JS
authors.lastname: Park
authors.forename: Jung-Do
authors.initials: JD
authors.lastname: Choi
authors.forename: Michael
authors.initials: M
authors.lastname: Dabrowski
authors.forename: William M
authors.initials: WM
authors.lastname: Atkins
authors.forename: Moon-Young
authors.initials: MY
authors.lastname: Yoon
mesh_terms: D019843:Archaeal Proteins / Q000378:metabolism; D004099:Dihydroxyacetone Phosphate / Q000737:chemistry / Q000378:metabolism; D005634:Fructose-Bisphosphate Aldolase / Q000378:metabolism*; D005985:Glyceraldehyde / Q000737:chemistry / Q000378:metabolism; D006600:Hexosephosphates / Q000378:metabolism*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D017017:Methanococcus / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D019843:Archaeal Proteins; D006600:Hexosephosphates; C048089:fuculose 1-phosphate; D005985:Glyceraldehyde; D004099:Dihydroxyacetone Phosphate; D005634:Fructose-Bisphosphate Aldolase