2.1.1.14 - 441323 2.1.1.14 an unusual-barrel structure in which the active site lies between the tops of the two (betaalpha)8 barrels 660333 2.1.1.14 binding of L-homocysteine or methionine results in conformational rearrangements at the amino acid binding pocket, moving the catalytic zinc into position to activate the thiol group. Active-site residues Asn126 and Tyr660 play key roles in catalysis 734490 2.1.1.14 cocrystallization with L-homocysteine or met and ternary complexes with folate substrates, sitting drop method 659400 2.1.1.14 hanging drop vapour diffusion method 671122 2.1.1.14 hanging-drop vapor diffusion method 720259 2.1.1.14 structures of native MetE in complex with either Zn2+ or Cd2+, at resolution limits of 2.10 A and 1.88 A, respectively. The monomeric protein contains two domains, each containing a (betaalpha)8 barrel core, and a long alpha-helical segment spans the length of the protein, connecting the domains. Zn2+ bound in the C-terminal domain exhibits tetrahedral coordination with the side chains of His652, Cys654, Glu676 and Cys737 755889 2.1.1.14 ternary complex with both substrates bound in a closed form of the enzyme. The closing is described in terms of a hinge between the N- and C-terminal TIM barrels and a rearrangement of key loops within the C domain 757428 2.1.1.14 vapor batch (microbatch) method using 25% poly(ethylene glycol) 4000, 0.2 M ammonium sulfate, and 0.1 M sodium acetate (pH 4.6) 676741